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AMD PSP: Firmware TPM Remote Code Execution via Crafted EK Certificate
- userbinator 9y agoAMD PSP is basically their equivalent to Intel's ME, so this is not surprising... but then it says This function is called from TPM2_CreatePrimary with user controlled data - a DER encoded [6] endorsement key (EK) certificate stored in the NV storage. If I understand correctly, this is related to SecureBoot and to do such operations with the keys and certificates, the user has to have physical access to the BIOS/UEFI setup already, correct?
- londons_explore 9y agoTPM's are supposed to be resistant to physical attacks. With this flaw, someone can just stick a bootable USB stick in your computer to mirror the LUKS/bitlocker disk drive and get access to the keys in the TPM which protect that drive.
- dfox 9y agoFor discrete TPMs the specification explicitly says that they are not required to be resistant to physical attacks (probably because that would require specifying what kinds of attacks it is supposed to be resistant to).
- jkolem2 9y agoI think Intel's ME is much more complex than AMD's PSP. Does anyone know if AMD's PSP has a full network stack and the ability to interact with network hardware independent of the main CPU's OS?
- moosingin3space 9y agoI had read somewhere that AMD PSP does not have Internet access.
- dogma1138 9y agoIt does, DASH is also arguably much less secure than Intel's RMT.
- moosingin3space 9y agoHmm, I did not know this. Good to know!
- rnhmjoj 9y agoIs there a documentation of what its capabilities are? I can't find anything specific about it.
- dogma1138 9y agoOf the remote management? Only this https://developer.amd.com/tools-for-dmtf-dash/ https://developer.amd.com/tools-for-dmtf-dash/ AMD hasn't really had any hardware for the enterprise for a long time so they are quite behind on many things. This is their free remote admin tool : https://community.amd.com/community/devgurus/dmtf-dash/blog/2017/06/08/amc-25-amd-management-console-release-announcement https://community.amd.com/community/devgurus/dmtf-dash/blog/... It can basically do quite a few things, change firmware, boot an image, redirect USB input and likely quite a few of other undocumented things. With Ryzen Pro launching soon I guess AMD would release a new suite of remote management software.
- rnhmjoj 9y agoThank you.
- dogma1138 9y agoYes, AMD's PSP runs a full OS which was made by Trustonic.
- kakarot 9y agoTrustonic is about as trustworthy a name as "Safecorp" or something similar. The name itself is just one big red flag.
- krylon 9y agoIt must feel weird to create an operating system that runs on a CPU inside a bigger CPU.
- dogma1138 9y agoTechnically if you count virtual machines as CPUs then every piece of Javascript etc. code runs in a CPU inside a CPU :P
- mtgx 9y agoThe PSP is already quite long in the tooth. I think AMD will switch to ARM's recently announced "SecurCore" soon, just like Qualcomm did for the Snapdragon 845: https://developer.arm.com/products/processors/cortex-m/sc300-processor https://developer.arm.com/products/processors/cortex-m/sc300...
- iancarroll 9y agoThat "processor" has been out for at least ten years.
- deleted 9y ago[deleted]
- mjg59 9y agoIt's not related to Secure Boot, no, so there's no requirement for physical access.
- Scaevolus 9y agoI think "remote" here means "host to TPM chip". Which is still bad, but not on the level of "install a rootkit on a powered-off machine" like some of the Intel ME exploits.
- deleted 9y ago[deleted]
- thrillgore 9y ago2018 is going to be a great year for zero day exploits.
- Tharkun 9y agoHopefully 2018 will be the year where CPU manufacturers finally start taking security seriously.
- zython 9y agodamnit AMD, you're supposed to be the undedog who came out victorious after this whole mess
- jhiska 9y agoOh, god. At this point I no longer trust ANY computer for mission-critical business at my company. We're going back to pen and paper. The extra safety makes the hassle worth it.
- mulmen 9y agoWhat makes you think pen and paper is secure?
- blattimwind 9y agoPen and paper in a good old fashioned steel cabinet (you can get those with some nice solid wood enclosing as well) require actual physical access to read. However, side channels exist. If you write classified information on a correspondence pad, then the pad itself becomes a classified item, too. Obviously.
- mulmen 9y agoWho gets keys to the cabinet? How do you know they haven't been duplicated? What if there is a fire? Do you keep a copy of the files somewhere? How do you control access to those?
- blattimwind 9y agoYou get literally the exact same set of problems with computers, plus all problems computers bring to the table for free.
- mulmen 9y agoYou're pretending pen and paper doesn't bring another set of problems of its own.
- blattimwind 9y agoNo, I'm just not exhaustively listing the advantages of computers, because (i) not what this thread is about (ii) by and large we're aware of them.
- phyller 9y agoLooks like it's already fixed. "Timeline ======== 09-28-17 - Vulnerability reported to AMD Security Team. 12-07-17 - Fix is ready. Vendor works on a rollout to affected partners. 01-03-18 - Public disclosure due to 90 day disclosure deadline."
- moby_click 9y agoFor a while, I was pretty excited about secure enclaves, as a tool before homomorphic encryption reaches practicality. If remote code execution on the PSP means broken remote attestation, that hope goes down the drain, quickly. Maybe, the keys in the PSP are still protected by secure computing technology, like ARM TrustZone…
- gatmne 9y agoUntil a vulnerability is found in ARM TrustZone.
- merb 9y agonot sure why somebody would want to use a fTPM over a dTPM. Especially since most computers now have a dTPM. (well my cheap 80 € mainboard can switch between fTPM and dTPM.)
- nimbius 9y agoThe Platform Security Processor (PSP) is built in on all Family 16h + systems (basically anything post-2013), and controls the main x86 core startup. PSP firmware is cryptographically signed with a strong key similar to the Intel ME. If the PSP firmware is not present, or if the AMD signing key is not present, the x86 cores will not be released from reset, rendering the system inoperable. The PSP is an ARM core
- JepZ 9y agoYeah, while it seems that every modern CPU is affected by the recently discovered vulnerabilities, Intel and AMD still refuse to release their source code for the ME and PSP. Therefore, everybody on this planet has to run hardware with a lot (by all odds) of unpublished zero-day vulnerabilities. And to make matters worse at least for Intel we have indications that those security wholes are the result of a calculated risk to afford a higher development velocity: https://danluu.com/cpu-bugs/ https://danluu.com/cpu-bugs/ This year is going to be fun...
- m-p-3 9y agoAnd AMD were confident the same issue from Intel ME would happen to them. Glad someone proved them wrong, and that hopefully we'll get a proper killswitch for these backdoors.
- jwilk 9y agoTimeline with a sane date format: 2017-09-28 - Vulnerability reported to AMD Security Team. 2017-12-07 - Fix is ready. Vendor works on a rollout to affected partners. 2018-01-03 - Public disclosure due to 90 day disclosure deadline.
- xchip 9y ago>Fix is ready. Vendor works on a rollout to affected partners.