PT-2026-40674 · F5 · Big-Ip

Published 2026-05-13 · Updated 2026-05-17 · CVE-2026-42919

Positive Technologies (AI Summary)

CVSS v3.1

6.7

Medium

Base vector

AV:N/AC:L/PR:H/UI:N/S:U/C:L/I:H/A:H

Name of the Vulnerable Software and Affected Versions F5 BIG-IP versions prior to 17.1.3.1 F5 BIG-IP versions prior to 17.5.1.4 F5 BIG-IP versions prior to 21.0.0.1

Description A stack-based overflow exists in F5 BIG-IP, which is a condition where a program writes more data to a buffer located on the stack than the buffer is allocated to hold. This issue may allow an authenticated attacker with administrative access to escalate their privileges and cross a security boundary.

Recommendations Update to version 17.1.3.1 or later. Update to version 17.5.1.4 or later. Update to version 21.0.0.1 or later.

Fix

Stack Overflow

Weakness Enumeration

CWE-121

Related Identifiers

CVE-2026-42919

Affected Products

Big-Ip

References · 3

• https://nvd.nist.gov/vuln/detail/CVE-2026-42919 · Security Note
• https://twitter.com/f1tym1/status/2056025525601055112 · Twitter Post
• https://my.f5.com/manage/s/article/K000158971 · Patch, Vendor Advisory