PT-2026-40651 · F5 · Big-Ip Next For Kubernetes+3

Published 2026-05-13 · Updated 2026-05-22 · CVE-2026-40629

Positive Technologies (AI Summary)

CVSS v3.1

7.5

High

Base vector

AV:N/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 BIG-IP Next SPK (affected versions not specified) BIG-IP Next CNF (affected versions not specified) BIG-IP Next for Kubernetes (affected versions not specified)

Description When SSL profiles are configured on a virtual server, undisclosed traffic can cause the virtual server to stop processing new client connections due to an issue with the allocation of resources.

Recommendations Update F5 BIG-IP to version 17.1.3.1 or later. Update F5 BIG-IP to version 17.5.1.4 or later. At the moment, there is no information about a newer version that contains a fix for this vulnerability for BIG-IP Next SPK, BIG-IP Next CNF, and BIG-IP Next for Kubernetes.

Fix

Allocation of Resources Without Limits

Weakness Enumeration

CWE-770

Related Identifiers

CVE-2026-40629

Affected Products

Big-Ip

Big-Ip Next Cnf

Big-Ip Next Spk

Big-Ip Next For Kubernetes

References · 4

• https://nvd.nist.gov/vuln/detail/CVE-2026-40629 · Security Note
• https://twitter.com/f1tym1/status/2055991605450936587 · Twitter Post
• https://twitter.com/f1tym1/status/2057750686821937603 · Twitter Post
• https://my.f5.com/manage/s/article/K000158978 · Patch, Vendor Advisory