12 ms·

Dear Linux Kernel CNA, what have you done?

97 points by odood 3y ago

alasarmas 3y ago
I hate to get all meta (no I don’t sorry not sorry), but there is 100% a thing where every word that means (a) some important thing and (b) some less important thing ends up being a word that, for the vast majority of people, carries something like the emotional impact of definition (a) and the actual meaning of definition (b). For example, “literally” now means “figuratively”, “scan” now means “skim”, “authentic” means “expensive”, and so on. It’s basically Gresham’s Law [0] where less-consequential definitions of words drive more-consequential definitions of the same out of the marketplace. 0. https://en.wikipedia.org/wiki/Gresham%27s_law https://en.wikipedia.org/wiki/Gresham%27s_law
bhaney 3y ago
> Known vulnerabilities are in practice defined as ‘something with a CVE’ Then change that definition and stop operating off of it. It has never been correct.
- deleted 3y ago
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- Retr0id 3y ago
  Most people don't get a choice of which legislation/regulations to comply with.
  - michaelt 3y ago
    There's plenty of people in that position, but they're all working at huge corporations. Nobody ends up having to chase things like SOC2 and PCI-DSS without getting paid for it. Why should unpaid volunteers working on the Linux kernel do compliance work for FAANG-sized companies without getting paid for it? If these companies want the reports carefully triaged, they can send some employees to carefully triage them.
    - Retr0id 3y ago
      Nobody (at least, not me) is calling for the Linux foundation to do additional work. They've taken it upon themselves to assign a CVE to every bugfix, and it's being pointed out that that doesn't seem to be helping anyone.
    - A1kmm 3y ago
      And these standards do not say "patch every time there is a CVE, even if you are not vulnerable". For example PCI-DSS says "New security vulnerabilities are identified using industry-recognized sources for security vulnerability information, including alerts from international and national computer emergency response teams (CERTs)", it doesn't specifically even mention CVE. A vulnerability / bug in an upstream component may or may not end up being a vulnerability in a complex system incorporating that component. A vulnerability in upstream functionality that is disabled (or not used, with no possible path through which an attacker could trigger the upstream vulnerability) in a particular system is not a vulnerability in that system. Standards like ISO27001, SOC2, and PCI-DSS generally ask teams to have processes to discover vulnerabilities, but not necessarily to patch things that are not vulnerabilities in practice.
viraptor 3y ago
While I understand the problems raised in this post, I think they're going a bit too far. The CVEs assigned to the kernel were already specific to various parts of it. You're not running linux-x.y.z, but rather linux-x.y.z + specific config. That means vendors already needed to look at CVEs and decide what applies to them and what doesn't. It's up to NVD records to include how likely something is to be a problem and give it some description / score. Choosing a random selection of CVEs posted so far... they look reasonable. They're actual issues and they'll potentially affect someone. This reminds me of the cookie banners situation. Many people complain about the cookie banners being visible rather than about the companies doing things that requires them to notify you. Now if you say you care about the published vulnerabilities, you get to actually see them all. And potentially change the policies around how you worked with them. (yes, it's not a great analogy, I'm not blaming linux for having each of those vulnerabilities)
- Avamander 3y ago
  > That means vendors already needed to look at CVEs and decide what applies to them and what doesn't. So many vendors don't and it's tedious to say the least.
- throwaway11460 3y ago
  Perhaps people don't care about companies doing it and they don't want to be notified about it?
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phh 3y ago
This article largely misses the point from the Linux kernel's point of view. They have always said "Every bug is a security bug". I don't know about more global content, but at Kernel Recipes (2019?) gregkh took a Pixel that was running latest Google security patches that contained all CVEs. Then looked at non-CVE patches he merged in his LTS. And it took him less than an hour to find a DoS vulnerability. I understand the author's frustration from the Linux Kernel community to not want to classify bugs, but the reality is that a huge portion of the bug fixes are actually security fixes [1], so between requiring 20% of the patches to be merged, and 100%, is there really a point? The author mentions Cyber Resilience Act, and I believe that Linux Kernel team created this CNA /on purpose/ to have an impact on the CRA. They believe that the only way to have a secure Linux Kernel is to have an up-to-date Linux kernel. (cf https://social.kernel.org/notice/ARWvggnOvXny0CUCIa https://social.kernel.org/notice/ARWvggnOvXny0CUCIa ). With the CRA enacted, doing such a every-bug-is-a-security-bug CNA is a way for them to enforce their view. [1] FWIW, my personal opinion there is that this shows that Linux's monolith architecture is getting old, but I see nothing that could reasonably replace it. I think that "the dream" would be to have a LKL-like linux "arch" to compile every driver as an independent process of Hurd, with GKI-like stable-ish ABI.
- Avamander 3y ago
  > They have always said "Every bug is a security bug". If you can't reason about your codebase to a sufficient extent to actually determine that then something is very wrong. If everything is a CVE, nothing is. That approach just wastes a lot of time and effort making people not so familiar with the codebase (as the maintainers) do triage. I hope they get burnt quick by this approach.
  - viraptor 3y ago
    > If you can't reason about your codebase to a sufficient extent to actually determine that then something is very wrong. The environment where we write critical code the way we do now is very wrong. It's actually not that easy to figure out if something is exploitable or not. What if you add heap grooming? What if you enable another specific feature? What if an application fights for the same lock? What if measuring the time it takes to fail allows you to defeat aslr? People use exploit chains rather than independent ones these days and there are examples of clever cases of single-byte overflows turning into RCE. Sure, there are going to be cases where you're really really sure something can't be used, because for example the bug only produces a null dereference and an oops. Then someone else comes along and proves you wrong https://googleprojectzero.blogspot.com/2023/01/exploiting-null-dereferences-in-linux.html https://googleprojectzero.blogspot.com/2023/01/exploiting-nu...
mnau 3y ago
CVE DOS - aka denial of service through legislative/regulatory requirements instead of technical attack is going to be fun. Edit: by that I mean filing bogus report or just non-security related CVEs. That is also reason why a lot of projects are trying to register themselves as CNA (see curl etc).
- Avamander 3y ago
  It's going to be fun when companies pick Windows instead of Linux because it doesn't cause an awful to handle patch cycle in contexts where things have to work within some regulatory bounds (that make pointless updates cost a lot of time, effort and money, maybe even cause risk to human life).
  - eqvinox 3y ago
    > It's going to be fun when companies pick Windows instead of Linux […] work within some regulatory bounds You can get FuSa (functional safety) certified Linux; to my knowledge this just does not exist for Windows. There may be other situations where the choice does exist, but considering Windows and Linux widely equivalent in this context is not possible. > maybe even cause risk to human life Neither Windows nor Linux are, to my knowledge, certified for SoL (safety-of-life) applications. And to no surprise considering this is close to (but not quite) a mathematical proof your system can't hang/crash/starve, which is pretty much impossible for anything beyond an RTOS with current tooling.
    - Avamander 3y ago
      > You can get FuSa (functional safety) certified Linux; And they're going to ask how much for the recertification for each CVE fixed? I doubt that'd be cheap. > Neither Windows nor Linux are, to my knowledge, certified for SoL (safety-of-life) applications. I didn't have exactly SoL applications in mind, there are plenty of other situations where the stability of a system could cause a risk. Be it just an emergency call center server or a field laptop for looking up license plates - can't leave them unpatched (especially with some of the new legislation) but also downtime from poor updates could be really bad.
raesene9 3y ago
For another opinion on this topic https://jericho.blog/2024/02/26/the-linux-cna-red-flags-since-2022/ https://jericho.blog/2024/02/26/the-linux-cna-red-flags-sinc... Having a large number of new, unscored, CVEs in the Linux kernel is going to make things... interesting. From their lists https://lore.kernel.org/linux-cve-announce/ https://lore.kernel.org/linux-cve-announce/ these just have a CVE and not really enough detail for anyone to assign a score without a lot of additional analysis, which reduces their usefulness. To an extent it could be suggested they're just exposing an existing flaw in the system (CVSS scores which may be taken to be scientifically applied, are actually just matters of opinion in many cases), but it will cause a lot of problems with automated tooling and compliance.
- the8472 3y ago
  > Notably, SyzScope has classified 183 bugs out of 1,170 fuzzerexposed bugs as high-risk. KOOBE has managed to generate 6 new exploits for previously non-exploitable bugs. While the rate is low it does show that some bugs were indeed exploitable without that being known to the kernel devs. If an attacker is willing to invest more time than the kernel devs combing through commits to find vulnerabilities in the some older stable kernel then a big unlabeled pile saying "there's probably a vulnerability in there, go update" is correct.
- aryca 3y ago
  This way of thinking is how almost everyone approaches CVEs, but is also out of date now. There are millions of open source projects (tens of millions really). This attitude of treating security bugs as some sort of special snowflake isn't realistic There are easily hundreds of thousands of security vulnerabilities fixed every year that get no IDs because the current process is rooted in security from 1999 (the number is probably way way higher, but you get the idea) Rather than obsessing over individual vulnerability IDs, we should be building systems that treat this data as one of many inputs to determining risk
  - raesene9 3y ago
    Accurately determining risk relies on decent starting data, otherwise you run the risk of Garbage-in, Garbage-out. Whilst things like VEX and EPSS can help, they are based on the starting point that is CVE assignment and CVSS score. I don't particularly think that CVE+CVSS has been the "right" way to do things ever (definitely not in the last 10 years) but my thoughts don't really matter whilst regulators and governments apply special significance to them, which they do. Security bugs are special if a regulator can deem you in non-compliance if you have too many of them. This is of course leaving the whole area of attackers who actively try to exploit them to one side :).
gtirloni 3y ago
> Because of this, the CVE assignment team is overly cautious and assign CVE numbers to any bugfix that they identify Shouldn't this strategy lead to the opposite? By being overly cautious they should only assign CVEs for real demonstrable security issues.
- martijnvds 3y ago
  You can think of it as a "fail-safe" situation. Being cautious here means "it's better to assign a CVE when it's not a vulnerability, than to NOT assign a CVE when it's actually a vulnerability"
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michaelt 3y ago
> Typically, security researchers are held to higher standards when disclosing vulnerabilities. The expectation is that CVEs are assigned for ‘meaningful’ security vulnerabilities, and not for any software fixes that ‘might’ be a security vulnerability. Maybe that's the aspiration, but it's clearly not the case in practice. I reported a firefox bug 12 years ago where a malicious SVG could cause a hang - basically a 22-year-old XML bomb, adapted to SVG patterns. My bug turned out to be a duplicate of a 16 year old firefox bug. No way of stealing user data. No sandbox escape. Not a crash that might indicate a buffer overrun. With a process per tab, it doesn't even crash the browser. It's just a file that takes a very long time to load - and it's not even an image type that user-generated-content sites like facebook and reddit allow you to upload. Reasonably enough, 12 years ago it was triaged as a minor performance issue. Apparently in 2023, this counts as a CVE.
- gertop 3y ago
  12 years ago, Firefox wasn't multi process. So your bug would likely freeze the entire browser, including the UI. Considering that, back then, Firefox reloaded all tabs back when you reopened it, it would keep freezing even if you force closed it. Fun times.
  - toast0 3y ago
    > Considering that, back then, Firefox reloaded all tabs back when you reopened it, it would keep freezing even if you force closed it. That was always an option, as I recall. I think a non-default option, too. Not sure when they started adding the question about if you wanted to restore when you started up after a crash/unsafe shutdown.
  - rincebrain 3y ago
    I actually kept such an SVG bomb around as a demonstration of how badly you could break browsers for many years, to anyone who claimed they were completely secure and unbreakable. I should go see what happens if I load it now, since what changed was less that it stopped breaking them and more that I stopped having the conversation with many people...
- 3y ago
kuschku 3y ago
Right now, the vast majority of CVEs reported are bullshit filed by wannabe security researchers for resumé padding. Look at all the useless CVSS 9.8's filed against curl. With LLMs, even more bogus reports get filed every single day. CVEs assigned to every linux commit are more valid than each and every one of those bogus CVEs. Each and every one of them is associated with an actual change in a security-critical project. If you want the flood of useless CVEs to stop, you have to clean your own house first.
- Avamander 3y ago
  Bad CVEs elsewhere aren't an excuse.
  - kuschku 3y ago
    It's not elsewhere, it's bad CVEs everywhere. Curl is just a particularly good example because they document it so well.
    - Avamander 3y ago
      There are many more good and useful CVEs. I'd also kindly request you to suggest a better system.
      - deleted 3y ago
        [deleted]
      - kuschku 3y ago
        Filing a CVE used to be a dialog between the researcher, developers, and third-party domain experts. Accepting every random LLM-generated report and granting it a 9.8 score is not useful in any way. I have to patch hundreds of CVEs in a month, and only a handful are actually valid. The vast majority is "CVSS 9.8: regex complexity explosion in $library" which my project only uses during build. But I've got to patch it, because it's definitely absolutely critical. While the standard library bug that causes SSL connections to fall back to TLS1.1 instead of TLS1.3 by default is considered WONTFIX and gets REJECTED for a CVE.
denton-scratch 3y ago
Is it true that the Linux Kernel has traditionally deprecated the idea of "security bugs"? I thought the kernel crew took the view that a bug is a bug. So perhaps this policy is a kind of spoiler response to efforts to require all security bugs to have a CVE allocated.
eqvinox 3y ago
Good. Forcing downstream consumers of open source projects to spend resources on identifying and fixing security issues is not just entirely appropriate, but direly needed. If you're already paying someone to maintain Linux for you, this shouldn't be causing that much trouble; it might need some contractual adjustments but you're already set up to get a stream of "good" updates. The patch frequency may be higher, but other people already do the majority of the work for you. If you were just ingesting Linux "for free"… well, tough luck. You're profiting from the work of others already, you don't get to complain about not being spoon fed exactly what you need. In practice, a small number of commercial entities (likely a mix of commercial distributions and designated security companies) will probably offer "Linux as a service". People could do the same work on their own, but that's not cost effective. Either way, this shift in responsibilities has been long overdue.
- Retr0id 3y ago
  Linux as a service is most of Redhat and Canonical's business models. grsecurity does this from a security angle specifically - in fact they're boasting about it on their homepage right now (fair enough!) >Are Your Products Drowning in Linux Kernel CVE Noise? >We know your products can't be updated every week based off unverified CVE information. Address true risk by protecting against entire classes of vulnerabilites and exploitation techniques. Our Pro Support ensures you make the most of attack surface reduction and our proactive defense in your products. https://grsecurity.net/ https://grsecurity.net/
dang 3y ago
Recent and related: Linux Is a CVE Numbering Authority (CNA) - https://news.ycombinator.com/item?id=39406088 https://news.ycombinator.com/item?id=39406088 - Feb 2024 (10 comments) The Linux kernel project becomes a CVE numbering authority - https://news.ycombinator.com/item?id=39361511 https://news.ycombinator.com/item?id=39361511 - Feb 2024 (24 comments)
tptacek 3y ago
The purpose of CVEs is to ensure that people discussing vulnerabilities are talking about the same thing. CVEs aren't a checklist, they aren't a perfect enumeration, and it shouldn't matter if a CVE is issued for a nonissue. People who are burdened by requirements to ship (or produce rolling updates) to address every Linux kernel CVE are living in a state of sin. It doesn't make sense for the kernel CNA to alter its behavior to accommodate them.
- amluto 3y ago
  I think I agree. Erring in the direction of too many CVEs means that people trying to get bug fixes rolled out won’t need to deal with the dreaded “ok, we understand the problem, but we can’t actually fix it in our systems until it has a CVE” that comes all too often from distributors.
- tsujamin 3y ago
  It does matter, because they are inputs into other processes, and the signal to noise has gone down. There’ll be a lot more time wasted in orgs triaging non-security-relevant bugs in the future.
  - tptacek 3y ago
    It does not matter, because the signal was never there or meant to be there to begin with. CVEs solve a problem of multiple researchers and developers talking past each other about the same vulnerability (or vulnerable subsystem or line of code). It has never been a reliable enumeration of vulnerabilities. Organizations triaging CVEs line-by-line are abusing the system. The system should not bend itself to accommodate that abuse; that just harms everybody else who isn't abusing it.
    - gnfargbl 3y ago
      Let's continue your reductive line of thinking. If the only purpose is to ensure that developers are talking about the same issue, then why does the kernel need need CVEs at all? Their existing bug tracking mechanisms should be entirely adequate, no?
throwawaaarrgh 3y ago
I just assume that there is always a 0day lurking in my kernel. If you can execute any code on my system I assume it's game over
sour-taste 3y ago
This article does a good job explaining the Linux kernel position on cves: https://lwn.net/Articles/961978/ https://lwn.net/Articles/961978/ The relevant part: > Kroah-Hartman put up a slide showing possible "fixes" for CVE numbers. The first, "ignore them", is more-or-less what is happening today. The next, option, "burn them down", could be brought about by requesting a CVE number for every patch applied to the kernel. They intend to burn down the cve system, and complaining about it is not a plan to stop it.
- fargle 3y ago
  "burn them down" is kind of a brilliant political move. on one hand, it's true to the "all bugs are security bugs (and the converse is obviously true)" position. on the other hand, it will demonstrably cause hassles for what i term the "checklist security" people. "oh noes we only have the budget for N CVEs per release and we must have NONE > $arbitrary-number". and so that's a very good thing because checklist-security like that is far worse than nothing at all. on the the other-other hand, in more legitimate, well engineered downstream user, a CVE for every bug may conversely actually help real security. "all" you have to do is evaluate every single potential security flaw's real actual applicability and impact for your use case. and if you can't afford that - faking it with a check-the-box mentality is no substitute. but maybe you can afford that? if so better data will probably help, not hurt. finally, the other concrete improvement is that the people closest to the product will be able to more accurately judge the CVE score and more quickly correct outliers. a local privilege escalation that requires enhanced privileges to execute is not an 8. i'd much rather have 1000 CVEs with appropriate scores than 10 that are massively overrated and stupid. of course, a simple one-dimensional metric is hogwash anyway, but - baby steps.
- deleted 3y ago
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codedokode 3y ago
It is often difficult to assess the consequences of a bug, especially in large and complicated project like an OS kernel. It could take lot of time, and it is easier just to fix the bug and err on the safe side by calling it a potential "vulnerability". Especially when nobody pays a bounty for proof-of-concept.
pingubob 3y ago
I think I speak for the whole 0day and 1day market when I say "Thank you Linux"
bogota 3y ago
I wonder how much time discussing if something is or isn’t a CVE has wasted. As and end user if you don’t have a script that causes an exploit for a given CVE i don’t care. I have had to patch too many systems from hypothetical issues ASAP!! because management wants to look like they know something
pingubob 3y ago
I think I speak for the whole 0day and 1day market when I say "Thank you for this idiocy, Linux community" In their attempt to get revenge on security researchers for 'being more important', they have made it much easier for us to keep our exploits on the market for longer than before. The idea that 'only the latest linux kernel is secure' is absolutely bananas, because it completely disregards the fact that legacy systems exist, they power very critical parts of our society, and they cannot be updated (as a general rule). Only components can be updated in-place. So, again: thank you for the free money and for making exploits have a longer shelf life.
whatshisface 3y ago
Oh great, now the previously lazy companies will pressure researchers to "not have discovered" bugs due to the legislatively required response to anything put into the system formally... and we will start hearing, "I don't use open source because it involves triage of too many CVEs. Michaelsoft never gives my engineers mandatory work."
motohagiography 3y ago
seems like they are creating noise and chaos in the infosec space to centralize their own role and discretion in "managing" it. Cynically, I'd bet there are more than a few less technical but academic operators on the board who would run this play.
guardiangod 3y ago
Has any one in this thread actually evaluated all ~320 CVEs since Feb 20? Because I have. And I literally just finished writing a filter script for MITRE's cve.org API output. 1. Most of the new CVEs have potential security concerns. At the very least, they would have been assigned a CVE if they were reported by an external researcher. 2. Many of them don't affect the older LTS branches. 3. I found 1 (1!) CVE that has a remote exploitation possibility. The rest are mostly local privilege exploit or DoS or crashes. 4. This Greg dude (heh) is backtracking to 2021 to flag bugs that have since been fixed. If your kernel repository is even semi up to date, you would have cut down the CVE count by 1/3. In my company, the majority consensus amongst the kernel developers is 'patch your shit and do rolling release. We are too busy to evaluate all the CVEs.' On the opposite end, are embedded hardware kernel developers who barely had their kernels working on existing hardware. Both sides make good arguments and I don't have any opinion I'd share. There are other ways to lessen the CVE workload. 1. Disable unused components with defconf or make menuconfig. 2. Don't stay on the bleeding edge branch (ie. 6.x) 3. Implement automatic minor version commit merges Your mileage may vary, but with these implemented, the workload is managable imo.
- mmc 3y ago
  > There are other ways to lessen the CVE workload. > 1. Disable unused components with defconf or make menuconfig. +1 for avoiding vulnerabilities, but were you saying this lessens the CVE evaluation workload? I'd love to hear about automation for evaluating CVEs based on a kernel config. I've done a fair amount of that manually and I'm not aware of any metadata in the CVE records (or in the CVE json in gregkh's new vulns repo) that includes config metadata.
_tk_ 3y ago
I cannot really speak to the "Radio Equipment Directive", but what the author claims or implies with regards to the Cyber Resilience Act is not correct. These Annexes explain the imposed Vulnerability Handling Processes imposed on manufacturers. The EU obviously only speaks about _exploitable_ vulnerabilities, because they know the problems of the CVE system all too well. Best of all, open source projects are actively excluded by the CRA. [2] "Open source projects will not be required to directly implement the mandated processes described in the CRA. But every commercial product made available in the EU which is built on top of those open source projects will." [1]: https://eur-lex.europa.eu/resource.html?uri=cellar:864f472b-34e9-11ed-9c68-01aa75ed71a1.0001.02/DOC_2&format=PDF https://eur-lex.europa.eu/resource.html?uri=cellar:864f472b-... [2]: https://eclipse-foundation.blog/2023/12/19/good-news-on-the-cyber-resilience-act/ https://eclipse-foundation.blog/2023/12/19/good-news-on-the-...
GrumpySloth 3y ago
To me the most disingenuous thing here on Linux’s part is that they won’t issue CVEs for vulnerabilities which aren’t fixed. And thus the latest Linux release is always tautologically CVE-free. Magic. Maybe at work I should raise the idea that our Jira bug tickets should have only one possible status: “fixed”. I’m learning from the best.

97 points by odood 3y ago

I hate to get all meta (no I don’t sorry not sorry), but there is 100% a thing where every word that means (a) some important thing and (b) some less important thing ends up being a word that, for the vast majority of people, carries something like the emotional impact of definition (a) and the actual meaning of definition (b). For example, “literally” now means “figuratively”, “scan” now means “skim”, “authentic” means “expensive”, and so on. It’s basically Gresham’s Law [0] where less-consequential definitions of words drive more-consequential definitions of the same out of the marketplace. 0. https://en.wikipedia.org/wiki/Gresham%27s_law https://en.wikipedia.org/wiki/Gresham%27s_law

bhaney 3y ago

> Known vulnerabilities are in practice defined as ‘something with a CVE’ Then change that definition and stop operating off of it. It has never been correct.

deleted 3y ago
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Retr0id 3y ago
Most people don't get a choice of which legislation/regulations to comply with.
- michaelt 3y ago
  There's plenty of people in that position, but they're all working at huge corporations. Nobody ends up having to chase things like SOC2 and PCI-DSS without getting paid for it. Why should unpaid volunteers working on the Linux kernel do compliance work for FAANG-sized companies without getting paid for it? If these companies want the reports carefully triaged, they can send some employees to carefully triage them.
  - Retr0id 3y ago
    Nobody (at least, not me) is calling for the Linux foundation to do additional work. They've taken it upon themselves to assign a CVE to every bugfix, and it's being pointed out that that doesn't seem to be helping anyone.
  - A1kmm 3y ago
    And these standards do not say "patch every time there is a CVE, even if you are not vulnerable". For example PCI-DSS says "New security vulnerabilities are identified using industry-recognized sources for security vulnerability information, including alerts from international and national computer emergency response teams (CERTs)", it doesn't specifically even mention CVE. A vulnerability / bug in an upstream component may or may not end up being a vulnerability in a complex system incorporating that component. A vulnerability in upstream functionality that is disabled (or not used, with no possible path through which an attacker could trigger the upstream vulnerability) in a particular system is not a vulnerability in that system. Standards like ISO27001, SOC2, and PCI-DSS generally ask teams to have processes to discover vulnerabilities, but not necessarily to patch things that are not vulnerabilities in practice.

viraptor 3y ago

While I understand the problems raised in this post, I think they're going a bit too far. The CVEs assigned to the kernel were already specific to various parts of it. You're not running linux-x.y.z, but rather linux-x.y.z + specific config. That means vendors already needed to look at CVEs and decide what applies to them and what doesn't. It's up to NVD records to include how likely something is to be a problem and give it some description / score. Choosing a random selection of CVEs posted so far... they look reasonable. They're actual issues and they'll potentially affect someone. This reminds me of the cookie banners situation. Many people complain about the cookie banners being visible rather than about the companies doing things that requires them to notify you. Now if you say you care about the published vulnerabilities, you get to actually see them all. And potentially change the policies around how you worked with them. (yes, it's not a great analogy, I'm not blaming linux for having each of those vulnerabilities)

Avamander 3y ago
> That means vendors already needed to look at CVEs and decide what applies to them and what doesn't. So many vendors don't and it's tedious to say the least.
throwaway11460 3y ago
Perhaps people don't care about companies doing it and they don't want to be notified about it?

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phh 3y ago

This article largely misses the point from the Linux kernel's point of view. They have always said "Every bug is a security bug". I don't know about more global content, but at Kernel Recipes (2019?) gregkh took a Pixel that was running latest Google security patches that contained all CVEs. Then looked at non-CVE patches he merged in his LTS. And it took him less than an hour to find a DoS vulnerability. I understand the author's frustration from the Linux Kernel community to not want to classify bugs, but the reality is that a huge portion of the bug fixes are actually security fixes [1], so between requiring 20% of the patches to be merged, and 100%, is there really a point? The author mentions Cyber Resilience Act, and I believe that Linux Kernel team created this CNA /on purpose/ to have an impact on the CRA. They believe that the only way to have a secure Linux Kernel is to have an up-to-date Linux kernel. (cf https://social.kernel.org/notice/ARWvggnOvXny0CUCIa https://social.kernel.org/notice/ARWvggnOvXny0CUCIa ). With the CRA enacted, doing such a every-bug-is-a-security-bug CNA is a way for them to enforce their view. [1] FWIW, my personal opinion there is that this shows that Linux's monolith architecture is getting old, but I see nothing that could reasonably replace it. I think that "the dream" would be to have a LKL-like linux "arch" to compile every driver as an independent process of Hurd, with GKI-like stable-ish ABI.

Avamander 3y ago
> They have always said "Every bug is a security bug". If you can't reason about your codebase to a sufficient extent to actually determine that then something is very wrong. If everything is a CVE, nothing is. That approach just wastes a lot of time and effort making people not so familiar with the codebase (as the maintainers) do triage. I hope they get burnt quick by this approach.
- viraptor 3y ago
  > If you can't reason about your codebase to a sufficient extent to actually determine that then something is very wrong. The environment where we write critical code the way we do now is very wrong. It's actually not that easy to figure out if something is exploitable or not. What if you add heap grooming? What if you enable another specific feature? What if an application fights for the same lock? What if measuring the time it takes to fail allows you to defeat aslr? People use exploit chains rather than independent ones these days and there are examples of clever cases of single-byte overflows turning into RCE. Sure, there are going to be cases where you're really really sure something can't be used, because for example the bug only produces a null dereference and an oops. Then someone else comes along and proves you wrong https://googleprojectzero.blogspot.com/2023/01/exploiting-null-dereferences-in-linux.html https://googleprojectzero.blogspot.com/2023/01/exploiting-nu...

mnau 3y ago

CVE DOS - aka denial of service through legislative/regulatory requirements instead of technical attack is going to be fun. Edit: by that I mean filing bogus report or just non-security related CVEs. That is also reason why a lot of projects are trying to register themselves as CNA (see curl etc).

Avamander 3y ago
It's going to be fun when companies pick Windows instead of Linux because it doesn't cause an awful to handle patch cycle in contexts where things have to work within some regulatory bounds (that make pointless updates cost a lot of time, effort and money, maybe even cause risk to human life).
- eqvinox 3y ago
  > It's going to be fun when companies pick Windows instead of Linux […] work within some regulatory bounds You can get FuSa (functional safety) certified Linux; to my knowledge this just does not exist for Windows. There may be other situations where the choice does exist, but considering Windows and Linux widely equivalent in this context is not possible. > maybe even cause risk to human life Neither Windows nor Linux are, to my knowledge, certified for SoL (safety-of-life) applications. And to no surprise considering this is close to (but not quite) a mathematical proof your system can't hang/crash/starve, which is pretty much impossible for anything beyond an RTOS with current tooling.
  - Avamander 3y ago
    > You can get FuSa (functional safety) certified Linux; And they're going to ask how much for the recertification for each CVE fixed? I doubt that'd be cheap. > Neither Windows nor Linux are, to my knowledge, certified for SoL (safety-of-life) applications. I didn't have exactly SoL applications in mind, there are plenty of other situations where the stability of a system could cause a risk. Be it just an emergency call center server or a field laptop for looking up license plates - can't leave them unpatched (especially with some of the new legislation) but also downtime from poor updates could be really bad.

raesene9 3y ago

For another opinion on this topic https://jericho.blog/2024/02/26/the-linux-cna-red-flags-since-2022/ https://jericho.blog/2024/02/26/the-linux-cna-red-flags-sinc... Having a large number of new, unscored, CVEs in the Linux kernel is going to make things... interesting. From their lists https://lore.kernel.org/linux-cve-announce/ https://lore.kernel.org/linux-cve-announce/ these just have a CVE and not really enough detail for anyone to assign a score without a lot of additional analysis, which reduces their usefulness. To an extent it could be suggested they're just exposing an existing flaw in the system (CVSS scores which may be taken to be scientifically applied, are actually just matters of opinion in many cases), but it will cause a lot of problems with automated tooling and compliance.

the8472 3y ago
> Notably, SyzScope has classified 183 bugs out of 1,170 fuzzerexposed bugs as high-risk. KOOBE has managed to generate 6 new exploits for previously non-exploitable bugs. While the rate is low it does show that some bugs were indeed exploitable without that being known to the kernel devs. If an attacker is willing to invest more time than the kernel devs combing through commits to find vulnerabilities in the some older stable kernel then a big unlabeled pile saying "there's probably a vulnerability in there, go update" is correct.
aryca 3y ago
This way of thinking is how almost everyone approaches CVEs, but is also out of date now. There are millions of open source projects (tens of millions really). This attitude of treating security bugs as some sort of special snowflake isn't realistic There are easily hundreds of thousands of security vulnerabilities fixed every year that get no IDs because the current process is rooted in security from 1999 (the number is probably way way higher, but you get the idea) Rather than obsessing over individual vulnerability IDs, we should be building systems that treat this data as one of many inputs to determining risk
- raesene9 3y ago
  Accurately determining risk relies on decent starting data, otherwise you run the risk of Garbage-in, Garbage-out. Whilst things like VEX and EPSS can help, they are based on the starting point that is CVE assignment and CVSS score. I don't particularly think that CVE+CVSS has been the "right" way to do things ever (definitely not in the last 10 years) but my thoughts don't really matter whilst regulators and governments apply special significance to them, which they do. Security bugs are special if a regulator can deem you in non-compliance if you have too many of them. This is of course leaving the whole area of attackers who actively try to exploit them to one side :).

gtirloni 3y ago

> Because of this, the CVE assignment team is overly cautious and assign CVE numbers to any bugfix that they identify Shouldn't this strategy lead to the opposite? By being overly cautious they should only assign CVEs for real demonstrable security issues.

martijnvds 3y ago
You can think of it as a "fail-safe" situation. Being cautious here means "it's better to assign a CVE when it's not a vulnerability, than to NOT assign a CVE when it's actually a vulnerability"

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michaelt 3y ago

> Typically, security researchers are held to higher standards when disclosing vulnerabilities. The expectation is that CVEs are assigned for ‘meaningful’ security vulnerabilities, and not for any software fixes that ‘might’ be a security vulnerability. Maybe that's the aspiration, but it's clearly not the case in practice. I reported a firefox bug 12 years ago where a malicious SVG could cause a hang - basically a 22-year-old XML bomb, adapted to SVG patterns. My bug turned out to be a duplicate of a 16 year old firefox bug. No way of stealing user data. No sandbox escape. Not a crash that might indicate a buffer overrun. With a process per tab, it doesn't even crash the browser. It's just a file that takes a very long time to load - and it's not even an image type that user-generated-content sites like facebook and reddit allow you to upload. Reasonably enough, 12 years ago it was triaged as a minor performance issue. Apparently in 2023, this counts as a CVE.

gertop 3y ago
12 years ago, Firefox wasn't multi process. So your bug would likely freeze the entire browser, including the UI. Considering that, back then, Firefox reloaded all tabs back when you reopened it, it would keep freezing even if you force closed it. Fun times.
- toast0 3y ago
  > Considering that, back then, Firefox reloaded all tabs back when you reopened it, it would keep freezing even if you force closed it. That was always an option, as I recall. I think a non-default option, too. Not sure when they started adding the question about if you wanted to restore when you started up after a crash/unsafe shutdown.
- rincebrain 3y ago
  I actually kept such an SVG bomb around as a demonstration of how badly you could break browsers for many years, to anyone who claimed they were completely secure and unbreakable. I should go see what happens if I load it now, since what changed was less that it stopped breaking them and more that I stopped having the conversation with many people...
3y ago

kuschku 3y ago

Right now, the vast majority of CVEs reported are bullshit filed by wannabe security researchers for resumé padding. Look at all the useless CVSS 9.8's filed against curl. With LLMs, even more bogus reports get filed every single day. CVEs assigned to every linux commit are more valid than each and every one of those bogus CVEs. Each and every one of them is associated with an actual change in a security-critical project. If you want the flood of useless CVEs to stop, you have to clean your own house first.

Avamander 3y ago
Bad CVEs elsewhere aren't an excuse.
- kuschku 3y ago
  It's not elsewhere, it's bad CVEs everywhere. Curl is just a particularly good example because they document it so well.
  - Avamander 3y ago
    There are many more good and useful CVEs. I'd also kindly request you to suggest a better system.
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    - kuschku 3y ago
      Filing a CVE used to be a dialog between the researcher, developers, and third-party domain experts. Accepting every random LLM-generated report and granting it a 9.8 score is not useful in any way. I have to patch hundreds of CVEs in a month, and only a handful are actually valid. The vast majority is "CVSS 9.8: regex complexity explosion in $library" which my project only uses during build. But I've got to patch it, because it's definitely absolutely critical. While the standard library bug that causes SSL connections to fall back to TLS1.1 instead of TLS1.3 by default is considered WONTFIX and gets REJECTED for a CVE.

denton-scratch 3y ago

Is it true that the Linux Kernel has traditionally deprecated the idea of "security bugs"? I thought the kernel crew took the view that a bug is a bug. So perhaps this policy is a kind of spoiler response to efforts to require all security bugs to have a CVE allocated.

eqvinox 3y ago

Good. Forcing downstream consumers of open source projects to spend resources on identifying and fixing security issues is not just entirely appropriate, but direly needed. If you're already paying someone to maintain Linux for you, this shouldn't be causing that much trouble; it might need some contractual adjustments but you're already set up to get a stream of "good" updates. The patch frequency may be higher, but other people already do the majority of the work for you. If you were just ingesting Linux "for free"… well, tough luck. You're profiting from the work of others already, you don't get to complain about not being spoon fed exactly what you need. In practice, a small number of commercial entities (likely a mix of commercial distributions and designated security companies) will probably offer "Linux as a service". People could do the same work on their own, but that's not cost effective. Either way, this shift in responsibilities has been long overdue.

Retr0id 3y ago
Linux as a service is most of Redhat and Canonical's business models. grsecurity does this from a security angle specifically - in fact they're boasting about it on their homepage right now (fair enough!) >Are Your Products Drowning in Linux Kernel CVE Noise? >We know your products can't be updated every week based off unverified CVE information. Address true risk by protecting against entire classes of vulnerabilites and exploitation techniques. Our Pro Support ensures you make the most of attack surface reduction and our proactive defense in your products. https://grsecurity.net/ https://grsecurity.net/

dang 3y ago

Recent and related: Linux Is a CVE Numbering Authority (CNA) - https://news.ycombinator.com/item?id=39406088 https://news.ycombinator.com/item?id=39406088 - Feb 2024 (10 comments) The Linux kernel project becomes a CVE numbering authority - https://news.ycombinator.com/item?id=39361511 https://news.ycombinator.com/item?id=39361511 - Feb 2024 (24 comments)

tptacek 3y ago

The purpose of CVEs is to ensure that people discussing vulnerabilities are talking about the same thing. CVEs aren't a checklist, they aren't a perfect enumeration, and it shouldn't matter if a CVE is issued for a nonissue. People who are burdened by requirements to ship (or produce rolling updates) to address every Linux kernel CVE are living in a state of sin. It doesn't make sense for the kernel CNA to alter its behavior to accommodate them.

amluto 3y ago
I think I agree. Erring in the direction of too many CVEs means that people trying to get bug fixes rolled out won’t need to deal with the dreaded “ok, we understand the problem, but we can’t actually fix it in our systems until it has a CVE” that comes all too often from distributors.
tsujamin 3y ago
It does matter, because they are inputs into other processes, and the signal to noise has gone down. There’ll be a lot more time wasted in orgs triaging non-security-relevant bugs in the future.
- tptacek 3y ago
  It does not matter, because the signal was never there or meant to be there to begin with. CVEs solve a problem of multiple researchers and developers talking past each other about the same vulnerability (or vulnerable subsystem or line of code). It has never been a reliable enumeration of vulnerabilities. Organizations triaging CVEs line-by-line are abusing the system. The system should not bend itself to accommodate that abuse; that just harms everybody else who isn't abusing it.
  - gnfargbl 3y ago
    Let's continue your reductive line of thinking. If the only purpose is to ensure that developers are talking about the same issue, then why does the kernel need need CVEs at all? Their existing bug tracking mechanisms should be entirely adequate, no?

throwawaaarrgh 3y ago

I just assume that there is always a 0day lurking in my kernel. If you can execute any code on my system I assume it's game over

sour-taste 3y ago

This article does a good job explaining the Linux kernel position on cves: https://lwn.net/Articles/961978/ https://lwn.net/Articles/961978/ The relevant part: > Kroah-Hartman put up a slide showing possible "fixes" for CVE numbers. The first, "ignore them", is more-or-less what is happening today. The next, option, "burn them down", could be brought about by requesting a CVE number for every patch applied to the kernel. They intend to burn down the cve system, and complaining about it is not a plan to stop it.

fargle 3y ago
"burn them down" is kind of a brilliant political move. on one hand, it's true to the "all bugs are security bugs (and the converse is obviously true)" position. on the other hand, it will demonstrably cause hassles for what i term the "checklist security" people. "oh noes we only have the budget for N CVEs per release and we must have NONE > $arbitrary-number". and so that's a very good thing because checklist-security like that is far worse than nothing at all. on the the other-other hand, in more legitimate, well engineered downstream user, a CVE for every bug may conversely actually help real security. "all" you have to do is evaluate every single potential security flaw's real actual applicability and impact for your use case. and if you can't afford that - faking it with a check-the-box mentality is no substitute. but maybe you can afford that? if so better data will probably help, not hurt. finally, the other concrete improvement is that the people closest to the product will be able to more accurately judge the CVE score and more quickly correct outliers. a local privilege escalation that requires enhanced privileges to execute is not an 8. i'd much rather have 1000 CVEs with appropriate scores than 10 that are massively overrated and stupid. of course, a simple one-dimensional metric is hogwash anyway, but - baby steps.
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codedokode 3y ago

It is often difficult to assess the consequences of a bug, especially in large and complicated project like an OS kernel. It could take lot of time, and it is easier just to fix the bug and err on the safe side by calling it a potential "vulnerability". Especially when nobody pays a bounty for proof-of-concept.

pingubob 3y ago

I think I speak for the whole 0day and 1day market when I say "Thank you Linux"

bogota 3y ago

I wonder how much time discussing if something is or isn’t a CVE has wasted. As and end user if you don’t have a script that causes an exploit for a given CVE i don’t care. I have had to patch too many systems from hypothetical issues ASAP!! because management wants to look like they know something

pingubob 3y ago

I think I speak for the whole 0day and 1day market when I say "Thank you for this idiocy, Linux community" In their attempt to get revenge on security researchers for 'being more important', they have made it much easier for us to keep our exploits on the market for longer than before. The idea that 'only the latest linux kernel is secure' is absolutely bananas, because it completely disregards the fact that legacy systems exist, they power very critical parts of our society, and they cannot be updated (as a general rule). Only components can be updated in-place. So, again: thank you for the free money and for making exploits have a longer shelf life.

whatshisface 3y ago

Oh great, now the previously lazy companies will pressure researchers to "not have discovered" bugs due to the legislatively required response to anything put into the system formally... and we will start hearing, "I don't use open source because it involves triage of too many CVEs. Michaelsoft never gives my engineers mandatory work."

motohagiography 3y ago

seems like they are creating noise and chaos in the infosec space to centralize their own role and discretion in "managing" it. Cynically, I'd bet there are more than a few less technical but academic operators on the board who would run this play.

guardiangod 3y ago

Has any one in this thread actually evaluated all ~320 CVEs since Feb 20? Because I have. And I literally just finished writing a filter script for MITRE's cve.org API output. 1. Most of the new CVEs have potential security concerns. At the very least, they would have been assigned a CVE if they were reported by an external researcher. 2. Many of them don't affect the older LTS branches. 3. I found 1 (1!) CVE that has a remote exploitation possibility. The rest are mostly local privilege exploit or DoS or crashes. 4. This Greg dude (heh) is backtracking to 2021 to flag bugs that have since been fixed. If your kernel repository is even semi up to date, you would have cut down the CVE count by 1/3. In my company, the majority consensus amongst the kernel developers is 'patch your shit and do rolling release. We are too busy to evaluate all the CVEs.' On the opposite end, are embedded hardware kernel developers who barely had their kernels working on existing hardware. Both sides make good arguments and I don't have any opinion I'd share. There are other ways to lessen the CVE workload. 1. Disable unused components with defconf or make menuconfig. 2. Don't stay on the bleeding edge branch (ie. 6.x) 3. Implement automatic minor version commit merges Your mileage may vary, but with these implemented, the workload is managable imo.

mmc 3y ago
> There are other ways to lessen the CVE workload. > 1. Disable unused components with defconf or make menuconfig. +1 for avoiding vulnerabilities, but were you saying this lessens the CVE evaluation workload? I'd love to hear about automation for evaluating CVEs based on a kernel config. I've done a fair amount of that manually and I'm not aware of any metadata in the CVE records (or in the CVE json in gregkh's new vulns repo) that includes config metadata.

_tk_ 3y ago

I cannot really speak to the "Radio Equipment Directive", but what the author claims or implies with regards to the Cyber Resilience Act is not correct. These Annexes explain the imposed Vulnerability Handling Processes imposed on manufacturers. The EU obviously only speaks about _exploitable_ vulnerabilities, because they know the problems of the CVE system all too well. Best of all, open source projects are actively excluded by the CRA. [2] "Open source projects will not be required to directly implement the mandated processes described in the CRA. But every commercial product made available in the EU which is built on top of those open source projects will." [1]: https://eur-lex.europa.eu/resource.html?uri=cellar:864f472b-34e9-11ed-9c68-01aa75ed71a1.0001.02/DOC_2&format=PDF https://eur-lex.europa.eu/resource.html?uri=cellar:864f472b-... [2]: https://eclipse-foundation.blog/2023/12/19/good-news-on-the-cyber-resilience-act/ https://eclipse-foundation.blog/2023/12/19/good-news-on-the-...

GrumpySloth 3y ago

To me the most disingenuous thing here on Linux’s part is that they won’t issue CVEs for vulnerabilities which aren’t fixed. And thus the latest Linux release is always tautologically CVE-free. Magic. Maybe at work I should raise the idea that our Jira bug tickets should have only one possible status: “fixed”. I’m learning from the best.