PT-2026-40644 · F5 · Big-Ip

Published 2026-05-13 · Updated 2026-05-17 · CVE-2026-40061

Positive Technologies (AI Summary)

CVSS v3.1

8.7

High

Base vector

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

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 An issue exists in an undisclosed iControl REST and BIG-IP TMOS Shell (tmsh) command when BIG-IP DNS is provisioned. An authenticated attacker with the Resource Administrator or Administrator role can execute arbitrary system commands with elevated privileges. In Appliance mode deployments, this can allow the attacker to 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

Command Injection

Weakness Enumeration

CWE-77

Related Identifiers

CVE-2026-40061

Affected Products

Big-Ip

References · 3

• https://nvd.nist.gov/vuln/detail/CVE-2026-40061 · Security Note
• https://my.f5.com/manage/s/article/K000160788 · Patch, Vendor Advisory
• https://twitter.com/f1tym1/status/2055991595766284339 · Twitter Post