OpenSSH 7.7 through 7.9 Integer Overflow or Wraparound Vulnerability


OpenSSH 7.7 through 7.9 and 8.x before 8.1, when compiled with an experimental key type, has a pre-authentication integer overflow if a client or server is configured to use a crafted XMSS key.


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This leads to memory corruption and local code execution because of an error in the XMSS key parsing algorithm. NOTE: the XMSS implementation is considered experimental in all released OpenSSH versions, and there is no supported way to enable it when building portable OpenSSH.

Vulnerable Systems:

OpenSSH 7.7 through 7.9 

CVE Information:


Disclosure Timeline:
Published Date:10/09/2019