Skip to content
VulniPulse
Critical9.8F5

Critical [CVE-2021-23008] BIG-IP: On version 15.1.x before 15.1.3, 14.1.x before 14.1.4, 13.1.x before 13.1.4, 12.1.x before 12.1.6, and all versions of 16.0.x…

This critical-severity F5 advisory covers CVE-2021-23008 affecting BIG-IP, APM.

CVE-2021-23008 Published May 10, 2021Updated by vendor Jun 17, 2026
Affected products & platforms
F5BIG-IP
Open vendor advisory

Android app · Google Play

Monitor future F5 CVEs from your phone.

Choose a whole vendor or a precise platform, then receive matching security advisories by phone notification, email, or both. Coverage follows 32 official vendor sources and 160+ reviewed platform categories.

Matching phone alertsOptional email delivery

Summary

On version 15.1.x before 15.1.3, 14.1.x before 14.1.4, 13.1.x before 13.1.4, 12.1.x before 12.1.6, and all versions of 16.0.x and 11.6.x., BIG-IP APM AD (Active Directory) authentication can be bypassed via a spoofed AS-REP (Kerberos Authentication Service Response) response sent over a hijacked KDC (Kerberos Key Distribution Center) connection or from an AD server compromised by an attacker.

Note: Software versions which have reached End of Technical Support (EoTS) are not evaluated.

Affected versions
  • 15.1.x
  • 14.1.x
  • 13.1.x
  • 12.1.x
  • all versions

Official advisory · high-confidence parse· fetched 2 months ago·verify at source

Fixed versions
  • 15.1.3
  • 14.1.4
  • 13.1.4
  • 12.1.6

Official advisory · high-confidence parse· fetched 2 months ago·verify at source

Mitigation

Upgrade to a fixed release: 15.1.3, 14.1.4, 13.1.4, 12.1.6. That is the remediation for this advisory.

The vendor advisory may list additional interim mitigations or workarounds not captured here — review it before change work.

Official advisory · high-confidence parse· fetched 2 months ago·verify at source

Discussion(0)

No comments yet. Share field notes, upgrade gotchas, or questions — verify against the vendor advisory before acting on community advice.

Sign in to join the discussion.