CVE-2019-6686: F5 BIG-IP Local Traffic Manager

Medium severity, CVSS 5.3. EPSS: 1% chance of exploitation in the next 30 days.

On BIG-IP versions 15.0.0-15.0.1.1, 14.1.0-14.1.2, 14.0.0-14.0.1, 13.1.0-13.1.3.1, the Traffic Management Microkernel (TMM) might stop responding after the total number of diameter connections and pending messages on a single virtual server has reached 32K.

Affected products

• F5 BIG-IP Local Traffic Manager: from 13.1.0, before 13.1.3.2 (fixed in 13.1.3.2); from 14.0.0, before 14.0.1.1 (fixed in 14.0.1.1); from 14.1.0, before 14.1.2.1 (fixed in 14.1.2.1); from 15.0.0, before 15.1.0 (fixed in 15.1.0)

Published 2019-12-23. Last modified 2026-06-17.