What is CVE-2026-40699?

CVE-2026-40699 is a medium-severity vulnerability in F5 Big-ip, classified under Improper Neutralization of Data within XPath Expressions (XPath Injection). CVSS score: 6.5/10. Published 2026-05-13.

How severe is CVE-2026-40699?

Medium severity. CVSS v3 base score is 6.5 out of 10.

XPath Injection in F5 Big-ip

CVE-2026-40699

A vulnerability exists in the undisclosed pages in the Configuration utility that may allow a low-privileged authenticated attacker to access to undisclosed sensitive information. Note: Software versions which have reached End of Technica…

EPSS: 0.001 (22.1th percentile) — read the EPSS interpretation.

CVSS v3 metric

CVSS v3 base score 6.5 (Medium). Vector: CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:N/A:N.

Affected products

F5 Big-ip — versions 21.1.0, 21.0.0, 17.5.0

Weakness classification (CWE)

CWE-643 — Improper Neutralization of Data within XPath Expressions (XPath Injection)

References

f5sirt@f5.com (vendor-advisory, patch)
f5sirt@f5.com (vendor-advisory, patch)

Frequently asked questions

What is CVE-2026-40699?: CVE-2026-40699 is a medium-severity vulnerability in F5 Big-ip, classified under Improper Neutralization of Data within XPath Expressions (XPath Injection). CVSS score: 6.5/10. Published 2026-05-13.
How severe is CVE-2026-40699?: Medium severity. CVSS v3 base score is 6.5 out of 10.