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TI-2011-00466 Aliases CVE-2011-0539GHSA-395x-3x8q-mv38

The key_certify function in usr.bin/ssh/key.c in OpenSSH 5.6 and 5.7, when generating…

Priority MEDIUM 43CWE-457Published · Updated

Key facts

Attack vector
Network
Privileges required
None
User interaction
None
Attack complexity
Low
Impact type
Information disclosure, Security bypass
Confidentiality · integrity · availability
High · None · None
Fix status
No fix listed

Attack profile from CVSS 3.1 · CISA ADP. Fix status from CNA. Impact type from CWE-457, CWE-264 and the CVSS impact.

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.

Why it matters now

Exploitation None reported CISA SSVC · not in CISA KEV
EPSS 0.01847 79th percentileScored 2026-11-07
Fix No fix listed No fixed version in the sources yet

SSVC decision points

CISA ADP · SSVC 2.0.3

Exploitation
None
Automatable
Yes
Technical impact
Partial

The decision (Track, Attend, Act) also depends on your mission and well-being impact; see CISA's SSVC guide.

Affected products

VendorProductAffected versionsFixed inStatusSource
——all versions—No fix listedCNA
  • — Vendor— Affected all versions Fixed in — No fix listed CNA

CPE configurations NVD · 2

CPEVersionsRoleVendor
cpe:2.3:a:openbsd:openssh:5.6:*:*:*:*:*:*:*5.6VulnerableOpenBSD
cpe:2.3:a:openbsd:openssh:5.7:*:*:*:*:*:*:*5.7VulnerableOpenBSD
  • cpe:2.3:a:openbsd:openssh:5.6:*:*:*:*:*:*:* Versions 5.6 Vulnerable ·OpenBSD
  • cpe:2.3:a:openbsd:openssh:5.7:*:*:*:*:*:*:* Versions 5.7 Vulnerable ·OpenBSD

Remediation

No fixed version listed by the sources yet.

Vendor assessments

Red Hat

Red Hat rating: Low. Red Hat's page for this CVE →

Not affected: 3 products
  • Red Hat Enterprise Linux 4
  • Red Hat Enterprise Linux 5
  • Red Hat Enterprise Linux 6

Timeline

  1. 2026-10-02 Threatist record created from CVE-2011-0539
  2. 2026-10-03 Alias added: GHSA-395x-3x8q-mv38

References

Patch 1

Advisory 2

Other 2

  • TI-2023-19792 The PKCS#11 feature in ssh-agent in OpenSSH before 9.3p2 has an insufficiently… CVSS 3.1CRITICAL 9.8
  • TI-2024-05929 Openssh: regresshion - race condition in ssh allows rce/dos CVSS 3.1HIGH 8.1
  • TI-2023-10601 OpenSSH server (sshd) 9.1 introduced a double-free vulnerability during… CVSS 3.1MEDIUM 6.5
  • TI-2018-11033 OpenSSH through 7.7 is prone to a user enumeration vulnerability due to not delaying… CVSS 3.1MEDIUM 5.9
  • TI-2016-08105 Untrusted search path vulnerability in ssh-agent.c in ssh-agent in OpenSSH before 7.4… CVSS 3.1HIGH 7.3
  • TI-2023-28040 In ssh in OpenSSH before 9.6, OS command injection might occur if a user name or host… CVSS 3.1MEDIUM 6.5
See all 145 →

Sources

This product uses the NVD API but is not endorsed or certified by the NVD. Sources and licences