PT-2026-40673 · F5 · Big-Ip

Published 2026-05-13 · Updated 2026-05-17 · CVE-2026-42781

Positive Technologies (AI Summary)

CVSS v3.1

6.5

Medium

Base vector

AV:A/AC:L/PR:N/UI:N/S:U/C:N/I:N/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 When embedded Packet Velocity Acceleration (ePVA) is configured, undisclosed local ethernet traffic can trigger an infinite loop in the Traffic Management Microkernel (TMM), leading to increased resource utilization of both ePVA and TMM.

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

Infinite Loop

Weakness Enumeration

CWE-835

Related Identifiers

CVE-2026-42781

Affected Products

Big-Ip

References · 3

• https://nvd.nist.gov/vuln/detail/CVE-2026-42781 · Security Note
• https://my.f5.com/manage/s/article/K000160862 · Patch, Vendor Advisory
• https://twitter.com/f1tym1/status/2056025515291488381 · Twitter Post