Auth bypass in F5 Big-Ip Access Policy Manager

CVE-2021-23008

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.

Vulnerability class: Broken Authentication

Published · last modified .

CVSS v3 metric

CVSS v3 base score 9.8 (Critical). Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H.

EPSS exploit prediction

EPSS: 0.013 (69.8th percentile), scored .

Low probability of exploitation in the next 30 days, but still tracked. 70th percentile — 69.8% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.

EPSS trend (30 days)EPSS over the last 30 days for CVE-2021-23008: held from 0.013 to 0.013.

EPSS over last 30 days · oldest: 0.013 · newest: 0.013 · change: 0.000

Affected products

  • F5 Big-Ip Access Policy Manager
  • Big-Ip Apm — versions 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.

Weakness classification (CWE)

Public proof-of-concept exploits

References

Frequently asked questions

What is CVE-2021-23008?
CVE-2021-23008 is a critical-severity vulnerability in F5 Big-Ip Access Policy Manager, classified under Improper Authentication. CVSS score: 9.8/10. Published 2021-05-10.
How severe is CVE-2021-23008?
Critical severity. CVSS v3 base score is 9.8 out of 10.
Is CVE-2021-23008 known to be exploited?
1 public proof-of-concept repositories are indexed. Not currently listed in the CISA KEV catalog.