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I'm posting this because within the past year, Symantec has gotten in hot water for issuing rogue certificates[1]. While Symantec has agreed to certificate tran

I'm posting this because within the past year, Symantec has gotten in hot water for issuing rogue certificates[1]. While Symantec has agreed to certificate transparency, Blue Coat is a known operator of MITM services they sell to nation-states, and this certificate would allow Blue Coat to issue arbitrary MITM certificates. It's not clear to me why Blue Coat would need to be a trusted CA by all systems and browsers, but given their own checkered history[2] I don't think it would be unreasonable to suggest they're going to use this for MITM purposes. [1] - https://security.googleblog.com/2015/09/improved-digital-certificate-security.html https://security.googleblog.com/2015/09/improved-digital-cer... [2] - https://en.wikipedia.org/w/index.php?title=Blue_Coat_Systems&oldid=721816010#Controversy https://en.wikipedia.org/w/index.php?title=Blue_Coat_Systems...

MichaelGG 10y ago
They have a cloud services platform, perhaps it's for that? Symantec would get destroyed if they issued a CA cert that was misused, right? Edit: This product says it does real-time traffic analysis for user transactions. It's understandable they want to make this as easy for customers as possible, just like CloudFlare. https://www.elastica.net/cloudsoc/-- https://www.elastica.net/cloudsoc/-- or maybe I'm misunderstanding what it does?
- mrb 10y ago
  Yes they have a cloud service: https://www.bluecoat.com/products-and-solutions/global-cloud-operations https://www.bluecoat.com/products-and-solutions/global-cloud... In fact, other than running a legit CA service, using this intermediate CA to intercept and decrypt traffic on their cloud is the only acceptable use of the intermediate CA I can think of, as long as they disclose to their cloud customers that they MitM TLS connections. After all, Blue Coat's cloud is their network, so they have the right to operate it the way they want. Any other use of the intermediate CA would be highly irresponsible/dangerous. For example if they used it in their SSL Visibility Appliance, any owner of the appliance could extract the CA private key from the appliance.
  - 0x0 10y ago
    Couldn't they implement something like cloudflare keyless ssl to keep this (horrible) ca private key... private?
    - mrb 10y ago
      This would keep the key private, but would not contain the potential for abuse. The appliance owner could still invoke whatever mechanism is used to generate certs for arbitrary hostnames.
  - mintplant 10y ago
    > In fact, other than running a legit CA service, using this intermediate CA to intercept and decrypt traffic on their cloud is the only acceptable use of the intermediate CA I can think of, as long as they disclose to their cloud customers that they MitM TLS connections. After all, Blue Coat's cloud is their network, so they have the right to operate it the way they want. Even that is silly - they don't need to be an intermediate CA to do that. Just require that their customers install a custom certificate.
  - Buge 10y ago
    I'm unclear about what you're saying. Are you saying it is OK for them to MITM traffic to https://google.com https://google.com on their network by issuing a google.com cert? That is definitely not OK. If they only issue certs for domains that belong to themselves or their customers, that is OK.
    - prdonahue 10y ago
      Notwithstanding key pinning (which I believe is even overridden by installed private roots), they can issue for google.com as long as they want so long as they get their users to install a private root.
      - Laforet 10y ago
        This, MITM using voluntarily installed trust anchors is one thing and explicitly allowed by google, creating a certificate for google.com that will be accepts by all TLS clients is not and Symantec have got in trouble before for doing this.
- deleted 10y ago
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- AaronFriel 10y ago
  Even Cloudflare doesn't use their own CA, but they have a relationship with Comodo; at least, from what I can tell on services I use with Cloudflare. If they just need to issue lots of certificates, or make it easy for client devices to get certificates, or even for their own cloud services, they could use LetsEncrypt. There are very few use cases where having your own CA is necessary, and for a company like Blue Coat, those reasons seem primarily nefarious.
  - prdonahue 10y ago
    We have relationships with Comodo, DigiCert, and GlobalSign. A large part of our Universal SSL issuance is currently through Comodo, which is probably what you noticed. (We've considered acquiring our own CA or subCA in the past but the audit requirements are quite onerous, at least after the first year, and sometimes it's nice to have someone handle certain aspects for you.) The most important thing to pay attention to here, with respect to Blue Coat, is the subscriber agreement they have signed with the CA AND the CPS that they write for their auditors. It'll dictate what they are and are not allowed to do with this subCA. If these are publicly trusted certificates, they will still need to pass—at minimum—domain control validation, e.g., can BC/their customers add an arbitrary DNS record or HTTP-accessible file for the zone being issued? If not, CA/B prohibits their issuance, so Symantec would get in huge trouble for allowing this. When you run your own subCA you are supposed to perform these checks yourself; it's up to their auditors (more in a sec) and Symantec to make sure they are performing these each and every time. Additionally, Blue Coat will need to pass a WebTrust audit as mandated by the CA/B Forum. The thoroughness of this audit depends on how much Blue Coat is taking over from Symantec. If they're, e.g., handling key material, the audit will be much the same the CAs themselves must do. If doing considerably less, the scope of the audit is considerably more constrained. I think these audits are released to the public as I remember Let's Encrypt doing so, but that may just be because i) they aren't a full blown directly browser trusted CA or ii) LE just decided to do so as it fits their ethos. You can find the relevant regulations that are imposed on public CAs here (look specifically for references to Subscriber Agreements): https://github.com/cabforum/documents/tree/master/docs https://github.com/cabforum/documents/tree/master/docs. I'd start with the "BRs" (Baseline Requirements) doc; the other, EV Guidelines are irrelevant here, and Bylaws apply to CA/B itself. Source: I manage CloudFlare's relationship with CAs and product manage our SSL/TLS related offerings. EDIT: Added reference to CPS, the Certification Practice Statement. This document is written and provided to the auditors, and includes controls to test, etc. Here's Symantec's for example (as linked within X509v3 in crt.sh): https://www.symauth.com/cps https://www.symauth.com/cps.
- JoshTriplett 10y ago
  > Symantec would get destroyed if they issued a CA cert that was misused, right? Assuming browsers are willing to actually follow through and do so, yes.
  - acveilleux 10y ago
    The big question is does the emperor have any clothes? My guess is they'd settle for blocking certs issued after a specific date, at least for a transition period. The alternative would block too much of the internet.
    - MichaelGG 10y ago
      If you really don't trust the CA, then you can't trust the issue date. At a minimum they could block EV certs from being honoured as EV which harms reputation and prevents a profitable line of business.
    - prdonahue 10y ago
      Trust me, Google would take action almost immediately after realizing what happened (if this were to actually go down). Take a look at Ryan Sleevi's previous posts on Symantec: 1. https://security.googleblog.com/2015/10/sustaining-digital-certificate-security.html?m=1 https://security.googleblog.com/2015/10/sustaining-digital-c... 2. https://security.googleblog.com/2015/12/proactive-measures-in-digital.html?m=1 https://security.googleblog.com/2015/12/proactive-measures-i... Ryan takes egregious violations of the BRs quite seriously. The CAs cross Google at their own risk. One day you find you're not trusted in Chrome anymore and their goes your business.
      - devishard 10y ago
        Blue Coat need only issue MITM certificates for one large client for a few days to both do a lot of damage and make a lot of money, and if that's their plan, what do they care if they aren't trusted in Chrome afterward?
- devishard 10y ago
  Security is not obtained by optimistically assuming actors are using their capabilities for good. Sure, there are legit ways they could use this, but the entire point of CAs is that they be trusted actors, and there are very strong reasons not to trust Blue Coat. Your comment is like discovering the fox has been given the keys to the henhouse and saying "Maybe the fox just wants to hang out with the hens".
  - mhkool 10y ago
    It is now simply a matter of time. How long will it take to find out that this certificate was used for a MITM attack? I suspect it will be less than 18 months. And 99% of the people will be 'shocked' :-)
deleted 10y ago
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beedogs 10y ago
Wow. I knew there was a reason I've always done all my work browsing via a tethered 4g connection and an SSH proxy.

MichaelGG 10y ago

They have a cloud services platform, perhaps it's for that? Symantec would get destroyed if they issued a CA cert that was misused, right? Edit: This product says it does real-time traffic analysis for user transactions. It's understandable they want to make this as easy for customers as possible, just like CloudFlare. https://www.elastica.net/cloudsoc/-- https://www.elastica.net/cloudsoc/-- or maybe I'm misunderstanding what it does?

mrb 10y ago
Yes they have a cloud service: https://www.bluecoat.com/products-and-solutions/global-cloud-operations https://www.bluecoat.com/products-and-solutions/global-cloud... In fact, other than running a legit CA service, using this intermediate CA to intercept and decrypt traffic on their cloud is the only acceptable use of the intermediate CA I can think of, as long as they disclose to their cloud customers that they MitM TLS connections. After all, Blue Coat's cloud is their network, so they have the right to operate it the way they want. Any other use of the intermediate CA would be highly irresponsible/dangerous. For example if they used it in their SSL Visibility Appliance, any owner of the appliance could extract the CA private key from the appliance.
- 0x0 10y ago
  Couldn't they implement something like cloudflare keyless ssl to keep this (horrible) ca private key... private?
  - mrb 10y ago
    This would keep the key private, but would not contain the potential for abuse. The appliance owner could still invoke whatever mechanism is used to generate certs for arbitrary hostnames.
- mintplant 10y ago
  > In fact, other than running a legit CA service, using this intermediate CA to intercept and decrypt traffic on their cloud is the only acceptable use of the intermediate CA I can think of, as long as they disclose to their cloud customers that they MitM TLS connections. After all, Blue Coat's cloud is their network, so they have the right to operate it the way they want. Even that is silly - they don't need to be an intermediate CA to do that. Just require that their customers install a custom certificate.
- Buge 10y ago
  I'm unclear about what you're saying. Are you saying it is OK for them to MITM traffic to https://google.com https://google.com on their network by issuing a google.com cert? That is definitely not OK. If they only issue certs for domains that belong to themselves or their customers, that is OK.
  - prdonahue 10y ago
    Notwithstanding key pinning (which I believe is even overridden by installed private roots), they can issue for google.com as long as they want so long as they get their users to install a private root.
    - Laforet 10y ago
      This, MITM using voluntarily installed trust anchors is one thing and explicitly allowed by google, creating a certificate for google.com that will be accepts by all TLS clients is not and Symantec have got in trouble before for doing this.
deleted 10y ago
[deleted]
AaronFriel 10y ago
Even Cloudflare doesn't use their own CA, but they have a relationship with Comodo; at least, from what I can tell on services I use with Cloudflare. If they just need to issue lots of certificates, or make it easy for client devices to get certificates, or even for their own cloud services, they could use LetsEncrypt. There are very few use cases where having your own CA is necessary, and for a company like Blue Coat, those reasons seem primarily nefarious.
- prdonahue 10y ago
  We have relationships with Comodo, DigiCert, and GlobalSign. A large part of our Universal SSL issuance is currently through Comodo, which is probably what you noticed. (We've considered acquiring our own CA or subCA in the past but the audit requirements are quite onerous, at least after the first year, and sometimes it's nice to have someone handle certain aspects for you.) The most important thing to pay attention to here, with respect to Blue Coat, is the subscriber agreement they have signed with the CA AND the CPS that they write for their auditors. It'll dictate what they are and are not allowed to do with this subCA. If these are publicly trusted certificates, they will still need to pass—at minimum—domain control validation, e.g., can BC/their customers add an arbitrary DNS record or HTTP-accessible file for the zone being issued? If not, CA/B prohibits their issuance, so Symantec would get in huge trouble for allowing this. When you run your own subCA you are supposed to perform these checks yourself; it's up to their auditors (more in a sec) and Symantec to make sure they are performing these each and every time. Additionally, Blue Coat will need to pass a WebTrust audit as mandated by the CA/B Forum. The thoroughness of this audit depends on how much Blue Coat is taking over from Symantec. If they're, e.g., handling key material, the audit will be much the same the CAs themselves must do. If doing considerably less, the scope of the audit is considerably more constrained. I think these audits are released to the public as I remember Let's Encrypt doing so, but that may just be because i) they aren't a full blown directly browser trusted CA or ii) LE just decided to do so as it fits their ethos. You can find the relevant regulations that are imposed on public CAs here (look specifically for references to Subscriber Agreements): https://github.com/cabforum/documents/tree/master/docs https://github.com/cabforum/documents/tree/master/docs. I'd start with the "BRs" (Baseline Requirements) doc; the other, EV Guidelines are irrelevant here, and Bylaws apply to CA/B itself. Source: I manage CloudFlare's relationship with CAs and product manage our SSL/TLS related offerings. EDIT: Added reference to CPS, the Certification Practice Statement. This document is written and provided to the auditors, and includes controls to test, etc. Here's Symantec's for example (as linked within X509v3 in crt.sh): https://www.symauth.com/cps https://www.symauth.com/cps.
JoshTriplett 10y ago
> Symantec would get destroyed if they issued a CA cert that was misused, right? Assuming browsers are willing to actually follow through and do so, yes.
- acveilleux 10y ago
  The big question is does the emperor have any clothes? My guess is they'd settle for blocking certs issued after a specific date, at least for a transition period. The alternative would block too much of the internet.
  - MichaelGG 10y ago
    If you really don't trust the CA, then you can't trust the issue date. At a minimum they could block EV certs from being honoured as EV which harms reputation and prevents a profitable line of business.
  - prdonahue 10y ago
    Trust me, Google would take action almost immediately after realizing what happened (if this were to actually go down). Take a look at Ryan Sleevi's previous posts on Symantec: 1. https://security.googleblog.com/2015/10/sustaining-digital-certificate-security.html?m=1 https://security.googleblog.com/2015/10/sustaining-digital-c... 2. https://security.googleblog.com/2015/12/proactive-measures-in-digital.html?m=1 https://security.googleblog.com/2015/12/proactive-measures-i... Ryan takes egregious violations of the BRs quite seriously. The CAs cross Google at their own risk. One day you find you're not trusted in Chrome anymore and their goes your business.
    - devishard 10y ago
      Blue Coat need only issue MITM certificates for one large client for a few days to both do a lot of damage and make a lot of money, and if that's their plan, what do they care if they aren't trusted in Chrome afterward?
devishard 10y ago
Security is not obtained by optimistically assuming actors are using their capabilities for good. Sure, there are legit ways they could use this, but the entire point of CAs is that they be trusted actors, and there are very strong reasons not to trust Blue Coat. Your comment is like discovering the fox has been given the keys to the henhouse and saying "Maybe the fox just wants to hang out with the hens".
- mhkool 10y ago
  It is now simply a matter of time. How long will it take to find out that this certificate was used for a MITM attack? I suspect it will be less than 18 months. And 99% of the people will be 'shocked' :-)

deleted 10y ago

[deleted]

beedogs 10y ago

Wow. I knew there was a reason I've always done all my work browsing via a tethered 4g connection and an SSH proxy.