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CVE-2011-0539

HIGH severity · CVSS 7.5 · CWE-264
7.5CVSS HIGH

Summary

The key_certify function in usr.bin/ssh/key.c in OpenSSH 5.6 and 5.7, when generating legacy certificates using the -t command-line option in ssh-keygen, does not initialize the nonce field, which might allow remote attackers to obtain sensitive stack memory contents or make it easier to conduct hash collision attacks.

Impact & exploitability

Attack vectorNetwork
Attack complexityLow
Privileges requiredNone
User interactionNone
Confidentiality impactHigh
Integrity impactNone
Availability impactNone
Exploit probability (EPSS)2%

CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N

Affected products we track (1)

Recommendation

Apply the vendor fix promptly. Open any affected product above for its exact safe version.

Official patch: http://www.openssh.com/txt/legacy-cert.adv ↗