{"id":"CVE-2016-6474","url":"https://www.cyber-defence.io/tools/cve/CVE-2016-6474","generatedAt":"2026-10-28T02:17:46.021Z","title":"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.","description":"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.","published":"2016-12-14T00:59:14.000Z","lastModified":"2026-06-17T00:51:15.000Z","status":"Modified","sourceIdentifier":"psirt@cisco.com","cvss":{"version":"3.0","score":7.3,"severity":"HIGH","vector":"CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:L/A:L"},"cwe":["CWE-287"],"affected":["cisco/ios"],"epss":{"score":0.01411,"percentile":0.72485,"date":"2026-10-26","history":[]},"kev":{"listed":false},"exploits":{"count":0,"verified":false,"firstPublished":null,"source":"Exploit-DB (https://gitlab.com/exploit-database/exploitdb)","entries":[]},"verdict":{"level":"high","text":"High impact if exploited, but EPSS currently rates exploitation as unlikely (1.41%). Schedule it in the normal patch cycle and watch for a rise in EPSS or a public exploit."},"changes":[],"references":[{"url":"http://www.securityfocus.com/bid/94773","tags":["Third Party Advisory","VDB Entry"],"source":"psirt@cisco.com"},{"url":"http://www.securitytracker.com/id/1037420","tags":["Third Party Advisory","VDB Entry"],"source":"psirt@cisco.com"},{"url":"https://tools.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-20161207-ios-xe-x509","tags":["Mitigation","Vendor Advisory"],"source":"psirt@cisco.com"},{"url":"http://www.securityfocus.com/bid/94773","tags":["Third Party Advisory","VDB Entry"],"source":"af854a3a-2127-422b-91ae-364da2661108"},{"url":"http://www.securitytracker.com/id/1037420","tags":["Third Party Advisory","VDB Entry"],"source":"af854a3a-2127-422b-91ae-364da2661108"},{"url":"https://tools.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-20161207-ios-xe-x509","tags":["Mitigation","Vendor Advisory"],"source":"af854a3a-2127-422b-91ae-364da2661108"}],"sources":{"nvd":"https://nvd.nist.gov/vuln/detail/CVE-2016-6474","epss":"https://www.first.org/epss/","kev":"https://www.cisa.gov/known-exploited-vulnerabilities-catalog","exploitdb":"https://www.exploit-db.com/"},"licence":"CC BY 4.0 — link back to the CVE Explorer if you publish the results; upstream data remains subject to its own terms."}