CVE-2026-39458

What it is

When a BIG-IP is configured with DNS caching (Such as a DNS profile with caching enabled, SSL Orchestrator, Advanced WAF DoS protection), 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.

At a glance

Exploitability

Can be exploited over the network without logging in. High risk of service disruption.

Exploit odds

0.3% chance of exploitation in the next 30 days (EPSS).

Fix

A patch, advisory or fixed version is referenced. Upgrade or apply it.

Timeline

1. 2026-05-13 16:16 UTC PublishedDisclosed publicly on CVE.org and NVD
2. 2026-10-26 17:10 UTC Last updatedMost recent change to the record

Details

Published

2026-05-13 16:16 UTC

Last modified

2026-10-26 17:10 UTC

Exploit probability

0.3% · EPSS, next 30 days

Weakness

CWE-824

Record status

Modified

Affected

• f5 big-ip Access Policy Manager ≤ 17.1.3
• f5 big-ip Access Policy Manager ≤ 17.5.1
• f5 big-ip Advanced Firewall Manager ≤ 17.1.3
• f5 big-ip Advanced Firewall Manager ≤ 17.5.1
• f5 big-ip Advanced Web Application Firewall ≤ 17.1.3
• f5 big-ip Advanced Web Application Firewall ≤ 17.5.1
• f5 big-ip Analytics ≤ 17.1.3
• f5 big-ip Analytics ≤ 17.5.1

Attack profile CVSS 4.0 · 8.7

Attack vector

Network

Complexity

Low

Attack requirements

None

Privileges needed

None

User interaction

None

Confidentiality

None

Integrity

None

Availability

High