Privilege escalation in F5 Big-Ip
CVE-2026-42406
A vulnerability exists in BIG-IP and BIG-IQ systems where a highly privileged, authenticated attacker with at least the Certificate Manager role can modify configuration objects that allow running arbitrary commands. Note: Software versions which have reached End of Technical Support (EoTS) are not evaluated.
Published · last modified .
CVSS v3 metric
CVSS v3 base score 8.7 (High). Vector: CVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:C/C:H/I:H/A:N.
EPSS exploit prediction
EPSS: 0.003 (15.5th percentile), scored .
Very low probability of exploitation in the next 30 days; routine patching cadence is appropriate. 15th percentile — 15.5% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.
EPSS over last 30 days · oldest: 0.002 · newest: 0.003 · change: +0.001
Affected products
- F5 Big-Ip — versions 21.1.0, 21.0.0, 17.5.0
- F5 Big-Ip Access Policy Manager — versions 21.0.0
- F5 Big-Ip Advanced Firewall Manager — versions 21.0.0
- F5 Big-Ip Advanced Web Application Firewall — versions 21.0.0
- F5 Big-Ip Analytics — versions 21.0.0
- F5 Big-Ip Application Acceleration Manager — versions 21.0.0
- F5 Big-Ip Application Security Manager — versions 21.0.0
- F5 Big-Ip Application Visibility And Reporting — versions 21.0.0
- F5 Big-Ip Automation Toolchain — versions 21.0.0
- F5 Big-Ip Carrier-Grade Nat — versions 21.0.0
Weakness classification (CWE)
References
- my.f5.com/manage/s/article/K000160971 (vendor-advisory, Mitigation, patch, Vendor Advisory)
Frequently asked questions
- What is CVE-2026-42406?
- CVE-2026-42406 is a high-severity vulnerability in F5 Big-Ip, classified under Privilege Defined With Unsafe Actions. CVSS score: 8.7/10. Published 2026-05-13.
- How severe is CVE-2026-42406?
- High severity. CVSS v3 base score is 8.7 out of 10.