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Instead of needing the honeypot openssh.patch at compile-time https://github.com/amlweems/xzbot/blob/main/openssh.patch
How did the exploit do this at runtime?
I know the chain was:
opensshd -> systemd for notifications -> xz included as transient dependency
How did liblzma.so.5.6.1 hook all the way back to openssh_RSA_verify when it was loaded into memory?
> It doesn't matter.
To understand the exact behavior and extend of the backdoor, this does matter. An end to end proof of how it works is exactly what was needed.
> A way to check if servers are vulnerable is probably by querying the package manager
Yes, this has been know since the initial report + later discovering what exact strings are present for the payload.
https://github.com/Neo23x0/signature-base/blob/master/yara/b...
> Not very sophisticated, but it'll work.
Unfortunately, we live in a world with closed-servers and appliances - being able as a customer or pen tester rule out certain class of security issues without having the source/insights available is usually desirable.
It's old and there are probably friendlier options out there now, but
https://github.com/moxie0/knockknock/blob/master/INSTALL
https://hn.algolia.com/?query=port%20knocking%20obscurity&ty...