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Qualys Security Advisory: MitM and DoS attacks against OpenSSH client and server (qualys.com)
4 points by mkeeter on Feb 18, 2025 | hide | past | favorite | 1 comment


MitM-able since 6.8 (December 2014) only if

> VerifyHostKeyDNS is "yes" or "ask" (it is "no" by default),

And DOS-able since 9.5 (2023) because of a new ping command.

> To confirm our suspicion, we adopted a dual strategy:

> - we manually audited all of OpenSSH's functions that use "goto", for missing resets of their return value;

> - we wrote a CodeQL query that automatically searches for functions that "goto out" without resetting their return value in the corresponding "if" code block.




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