5 ms·

Never think HTTPS will save you from proxies built by attackers... This may make it much simpler...

by SebFender 2y ago

SteveNuts 2y ago
Wouldn’t there still need to be a major vulnerability with the TLS library your client is using?
- supriyo-biswas 2y ago
  You can obtain a certificate for the domain in question (easier if you are a nation-state) and MITM that specific user.
  - theamk 2y ago
    ... but you need to MITM server to obtain certificate, and if you can MITM server, why bother with user's wifi?
    - supriyo-biswas 2y ago
      Because it’s easier that the server be MITMed for a shorter duration to prevent discovery[1]. It’s also easier if you can just strong arm the CA to issue a certificate or have the shady CA issue it[2][3]. [1] http://notes.valdikss.org.ru/jabber.ru-mitm/ http://notes.valdikss.org.ru/jabber.ru-mitm/ [2] https://www.wired.com/2010/03/packet-forensics/ https://www.wired.com/2010/03/packet-forensics/ [3] https://bugzilla.mozilla.org/show_bug.cgi?id=1391063 https://bugzilla.mozilla.org/show_bug.cgi?id=1391063
  - yjftsjthsd-h 2y ago
    How does one bypass certificate transparency? I tend to exclude state actors from my threat models (1. they tend to be the all-powerful boogeyman that bypasses all threat models anyways, and 2. I doubt that the NSA is going to get you by way of coffee shop wifi) but I'm actually struggling to see how even they would bypass this particular protection; if Chrome only trusts CT-logged certs, even a targeted one-off is likely to be discovered (albeit, AIUI, after the fact).
theamk 2y ago
Sure they will, given Chrome's requirement for CT logs, any attacker-issued certificates will be logged, someone will find the suspicious record, and the method will likely be burned from all the publicity. I have no doubt that there maybe a few dozen people in the entire world who would get attacked this way, but the chances it would be me are pretty much zero.
- 8organicbits 2y ago
  How often are you reviewing the CT logs for your domains? I posit that's rare.
  - immibis 2y ago
    BTW this attack actually happened with jabber.ru - "law" "enforcement" physically intercepted their Ethernet port, then they got to use their IP address and could issue new certificates.
    - debatem1 2y ago
      Do you happen to have a link or any other information about this?
      - immibis 2y ago
        https://notes.valdikss.org.ru/jabber.ru-mitm/ https://notes.valdikss.org.ru/jabber.ru-mitm/ https://news.ycombinator.com/item?id=37961166 https://news.ycombinator.com/item?id=37961166
    - 8organicbits 2y ago
      Rare was intended to refer to "the monitoring of CT logs". The CA system doesn't protect against an adversary who has physical control of your system.

Never think HTTPS will save you from proxies built by attackers... This may make it much simpler...

SteveNuts 2y ago

Wouldn’t there still need to be a major vulnerability with the TLS library your client is using?

supriyo-biswas 2y ago
You can obtain a certificate for the domain in question (easier if you are a nation-state) and MITM that specific user.
- theamk 2y ago
  ... but you need to MITM server to obtain certificate, and if you can MITM server, why bother with user's wifi?
  - supriyo-biswas 2y ago
    Because it’s easier that the server be MITMed for a shorter duration to prevent discovery[1]. It’s also easier if you can just strong arm the CA to issue a certificate or have the shady CA issue it[2][3]. [1] http://notes.valdikss.org.ru/jabber.ru-mitm/ http://notes.valdikss.org.ru/jabber.ru-mitm/ [2] https://www.wired.com/2010/03/packet-forensics/ https://www.wired.com/2010/03/packet-forensics/ [3] https://bugzilla.mozilla.org/show_bug.cgi?id=1391063 https://bugzilla.mozilla.org/show_bug.cgi?id=1391063
- yjftsjthsd-h 2y ago
  How does one bypass certificate transparency? I tend to exclude state actors from my threat models (1. they tend to be the all-powerful boogeyman that bypasses all threat models anyways, and 2. I doubt that the NSA is going to get you by way of coffee shop wifi) but I'm actually struggling to see how even they would bypass this particular protection; if Chrome only trusts CT-logged certs, even a targeted one-off is likely to be discovered (albeit, AIUI, after the fact).

theamk 2y ago

Sure they will, given Chrome's requirement for CT logs, any attacker-issued certificates will be logged, someone will find the suspicious record, and the method will likely be burned from all the publicity. I have no doubt that there maybe a few dozen people in the entire world who would get attacked this way, but the chances it would be me are pretty much zero.

8organicbits 2y ago
How often are you reviewing the CT logs for your domains? I posit that's rare.
- immibis 2y ago
  BTW this attack actually happened with jabber.ru - "law" "enforcement" physically intercepted their Ethernet port, then they got to use their IP address and could issue new certificates.
  - debatem1 2y ago
    Do you happen to have a link or any other information about this?
    - immibis 2y ago
      https://notes.valdikss.org.ru/jabber.ru-mitm/ https://notes.valdikss.org.ru/jabber.ru-mitm/ https://news.ycombinator.com/item?id=37961166 https://news.ycombinator.com/item?id=37961166
  - 8organicbits 2y ago
    Rare was intended to refer to "the monitoring of CT logs". The CA system doesn't protect against an adversary who has physical control of your system.