F5 BIG-IP TMM Crash via Undisclosed SIP Traffic (CVE-2026-40423)
CVE-2026-40423 Published on May 13, 2026

BIG-IP SIP profile vulnerability
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.

Vendor Advisory NVD

Vulnerability Analysis

CVE-2026-40423 can be exploited with network access, and does not require authorization privileges or user interaction. This vulnerability is considered to have a low attack complexity. The potential impact of an exploit of this vulnerability is considered to have no impact on confidentiality and integrity, and a high impact on availability.

Attack Vector:
NETWORK
Attack Complexity:
LOW
Privileges Required:
NONE
User Interaction:
NONE
Scope:
UNCHANGED
Confidentiality Impact:
NONE
Integrity Impact:
NONE
Availability Impact:
HIGH

Weakness Type

Allocation of Resources Without Limits or Throttling

The software allocates a reusable resource or group of resources on behalf of an actor without imposing any restrictions on the size or number of resources that can be allocated, in violation of the intended security policy for that actor.


Products Associated with CVE-2026-40423

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F5 Networks Big Ip
 

Affected Versions

F5 BIG-IP: