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.,…

published 2021-05-10 5y ago modified 2026-06-17 4mo ago also EUVD-2021-10126

cvss: 9.8; version 3.1, NVD
cisa kev: Not listed; not in CISA's catalog
epss: 1.3%; EPSS 1.3% chance of exploitation in 30 days, percentile 71%
public exploits: 0; none known

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.

Patch / fix

fixed in 1

f5 big-ip_access_policy_manager 11.6.5, 12.1.5, 13.1.3, 14.1.3, 15.1.2, 16.0.1

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Exploit prediction

1.33% chance of exploitation in the next 30 days, higher than 71% of all scored CVEs (FIRST EPSS, 2026-11-09).

CVSS scores

assigned by	version	score	vector
NVD	3.1	9.8	CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
NVD	2.0	7.5	AV:N/AC:L/Au:N/C:P/I:P/A:P

Affected products

n/a BIG-IP APM

Classification

Weakness

CWE-287 Improper Authentication

References

support.f5.com /csp/article/K51213246
vendor-advisory

Sources

CVE List CVE-2021-23008
NVD CVE-2021-23008

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