Deserialization in F5 Big-Ip
CVE-2026-41957
An authenticated remote code execution vulnerability through undisclosed vectors exists in the BIG-IP and BIG-IQ Configuration utility. Note: Software versions which have reached End of Technical Support (EoTS) are not evaluated.
Vulnerability class: Insecure Deserialization
Published · last modified .
CVSS v3 metric
CVSS v3 base score 8.8 (High). Vector: CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H.
EPSS exploit prediction
EPSS: 0.009 (58.2th percentile), scored .
Very low probability of exploitation in the next 30 days; routine patching cadence is appropriate. 58th percentile — 58.2% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.
EPSS over last 30 days · oldest: 0.005 · newest: 0.009 · change: +0.004
Affected products
- F5 Big-Ip — versions 21.0.0, 17.5.0, 17.1.0
- F5 Big-Ip Access Policy Manager
- F5 Big-Ip Advanced Firewall Manager
- F5 Big-Ip Advanced Web Application Firewall
- F5 Big-Ip Analytics
- F5 Big-Ip Application Acceleration Manager
- F5 Big-Ip Application Security Manager
- F5 Big-Ip Application Visibility And Reporting
- F5 Big-Ip Automation Toolchain
- F5 Big-Ip Carrier-Grade Nat
Weakness classification (CWE)
References
- my.f5.com/manage/s/article/K000156761 (vendor-advisory, Mitigation, patch, Vendor Advisory)
Frequently asked questions
- What is CVE-2026-41957?
- CVE-2026-41957 is a high-severity vulnerability in F5 Big-Ip, classified under Deserialization of Untrusted Data. CVSS score: 8.8/10. Published 2026-05-13.
- How severe is CVE-2026-41957?
- High severity. CVSS v3 base score is 8.8 out of 10.