Novel Terrapin attack uses prefix truncation to downgrade the security of SSH channels.
  • Piatro@programming.devEnglish
    0·
    11 months ago

    Bit of an alarmist headline here. The vulnerability has been patched in the most common clients (openssh) and it was because the protocol wasn’t being implemented correctly. To say that the SSH protocol “just got a lot weaker” is just not true.

    • Eager Eagle@lemmy.worldOPEnglish
      0·
      11 months ago

      It doesn’t look that simple to me. From the Terrapin paper:

      Although we suggest backward-compatible countermea- sures to stop our attacks, we note that the security of the SSH protocol would benefit from a redesign from scratch. This redesign should be guided by all findings and insights from both practical and theoretical security analysis, in a similar manner as was done for TLS 1.3.

      It seems the protocol itself needs a revision and implementation-specific patches are easier and less-than-ideal solutions.

      One could argue that even these solutions they provide are already changes to the protocol, and not just fixes to implementation bugs. Both the Sequence Number Reset and Full Transcript Hash add or change functionality at the communication protocol level, rather than simply covering corner cases.