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TI-2016-05555 Aliases CVE-2016-6474GHSA-xqx5-4vvj-rqwr

Improper authentication in Cisco IOS

Priority LOW 35CWE-287Published · Updated

Key facts

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

Attack profile from CVSS 3.0 · NVD. Fix status from CNA. Impact type from CWE-287.

Summary

A vulnerability in the implementation of X.509 Version 3 for SSH authentication functionality in Cisco IOS and IOS XE Software could allow an unauthenticated, remote attacker to bypass authentication on an affected system. More Information: CSCuv89417. Known Affected Releases: 15.5(2.25)T. Known Fixed Releases: 15.2(4)E1 15.2(4)E2 15.2(4)E3 15.2(4)EA4 15.2(4.0r)EB 15.2(4.1.27)EB 15.2(4.4.2)EA4 15.2(4.7.1)EC 15.2(4.7.2)EC 15.2(5.1.1)E 15.2(5.5.63)E 15.2(5.5.64)E 15.4(1)IA1.80 15.5(3)M1.1 15.5(3)M2 15.5(3)S1.4 15.5(3)S2 15.6(0.22)S0.12 15.6(1)T0.1 15.6(1)T1 15.6(1.15)T 15.6(1.17)S0.7 15.6(1.17)SP 15.6(1.22.1a)T0 15.6(2)S 15.6(2)SP 16.1(1.24) 16.1.2 16.2(0.247) 16.3(0.11) 3.8(1)E Denali-16.1.2.

Why it matters now

EPSS 0.01411 72nd percentileScored 2026-11-07
Fix No fix listed No fixed version in the sources yet

SSVC decision points

Not available: CISA has not published SSVC decision points for this record.

Affected products

VendorProductAffected versionsFixed inStatusSource
—Cisco IOSCisco IOS—No fix listedCNA
  • Cisco IOS Vendor— Affected Cisco IOS Fixed in — No fix listed CNA

CPE configurations NVD · 1

CPEVersionsRoleVendor
cpe:2.3:o:cisco:ios:15.5\(2.25\)t:*:*:*:*:*:*:*15.5(2.25)tVulnerableCisco
  • cpe:2.3:o:cisco:ios:15.5\(2.25\)t:*:*:*:*:*:*:* Versions 15.5(2.25)t Vulnerable ·Cisco

Remediation

No fixed version listed by the sources yet.

Timeline

  1. 2026-10-02 Threatist record created from CVE-2016-6474
  2. 2026-10-03 Alias added: GHSA-xqx5-4vvj-rqwr

References

Advisory 1

  • TI-2018-00138 Improper input validation in Cisco IOS and IOS XE KEVCVSS 3.1CRITICAL 9.8
  • TI-2017-09019 Improper input validation in Cisco IOS and IOS XE KEVCVSS 3.1CRITICAL 9.8
  • TI-2017-02977 Improper input validation in Cisco IOS and IOS XE Software KEVCVSS 3.1CRITICAL 9.8
  • TI-2018-00135 Memory corruption in Cisco IOS, IOS XE, and IOS XR KEVCVSS 3.1HIGH 8.8
  • TI-2017-04499 Memory corruption in Cisco IOS KEVCVSS 3.1HIGH 8.8
  • TI-2017-04498 Memory corruption in Cisco IOS KEVCVSS 3.1HIGH 8.8
See all 617 →

Sources

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