Vulnerability · Published May 13, 2026 · Assigned by f5

CVE-2026-40423BIG-IP SIP profile vulnerability

High 7.5

In plain English

A high-severity resource allocation without limits in BIG-IP from F5. There are no confirmed reports of exploitation so far. The chance it is exploited in the next 30 days is estimated at 0.3% (higher than 18% of all known vulnerabilities).

Severity (CVSS 3.1)7.5High
Exploit odds (30 days)0.3%top 81.8% of all CVEs
Exploited in the wildNo reportsCISA SSVC: none
Attack toolingNoneno public tooling known

Official description

When a SIP profile is configured on a virtual server, undisclosed traffic can cause the Traffic Management Microkernel (TMM) to terminate.  Note: Software versions which have reached End of Technical Support (EoTS) are not evaluated.

Affected products (as reported)

VendorProductVersions
F5 BIG-IP 21.0.0 – before 21.0.0.217.5.0 – before 17.5.1.617.1.0 – before 17.1.3.216.1.0 – before *

Weakness: CWE-770 · Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H

References