CVE-2019-6623

Severity: high (CVSS 7.5 v3.1)
Exploited in the wild: not listed in CISA KEV
EPSS: 2.5% probability of exploitation in the next 30 days
Public exploit or detection template: none known
Published: 2019-07-02 · updated 2026-06-17

Description

On BIG-IP 14.1.0-14.1.0.5, 14.0.0-14.0.0.4, 13.0.0-13.1.1.4, and 12.1.0-12.1.4, undisclosed traffic sent to BIG-IP iSession virtual server may cause the Traffic Management Microkernel (TMM) to restart, resulting in a Denial-of-Service (DoS).

Affected products

F5 BIG-IP APM: from 12.1.0 through 12.1.4; from 13.0.0 through 13.1.1.4; from 14.0.0 through 14.0.0.4; from 14.1.0 through 14.1.0.5
BIG-IP: from 12.1.0 through 12.1.4; from 13.0.0 through 13.1.1.4; from 14.0.0 through 14.0.0.4; from 14.1.0 through 14.1.0.5
F5 Big-Ip Analytics: from 12.1.0 through 12.1.4; from 13.0.0 through 13.1.1.4; from 14.0.0 through 14.0.0.4; from 14.1.0 through 14.1.0.5
F5 Networks, Inc. BIG-IP (AAM): from 12.1.0 through 12.1.4; from 13.0.0 through 13.1.1.4; from 14.0.0 through 14.0.0.4; from 14.1.0 through 14.1.0.5
BIG-IP ASM: from 12.1.0 through 12.1.4; from 13.0.0 through 13.1.1.4; from 14.0.0 through 14.0.0.4; from 14.1.0 through 14.1.0.5
F5 BIG-IP DNS: from 12.1.0 through 12.1.4; from 13.0.0 through 13.1.1.4; from 14.0.0 before 14.0.0.4; from 14.1.0 through 14.1.0.5 — fixed in 14.0.0.4
F5 Big-Ip Edge Gateway: from 12.1.0 through 12.1.4; from 13.0.0 through 13.1.1.4; from 14.0.0 through 14.0.0.4; from 14.1.0 through 14.1.0.5
F5 Big-Ip Fraud Protection Service: from 12.1.0 through 12.1.4; from 13.0.0 through 13.1.1.4; from 14.0.0 through 14.0.0.4; from 14.1.0 through 14.1.0.5
F5 Big-Ip Global Traffic Manager: from 12.1.0 through 12.1.4; from 13.0.0 through 13.1.1.4; from 14.0.0 through 14.0.0.4; from 14.1.0 through 14.1.0.5
F5 Big-Ip Link Controller: from 12.1.0 through 12.1.4; from 13.0.0 through 13.1.1.4; from 14.0.0 through 14.0.0.4; from 14.1.0 through 14.1.0.5
F5 BIG-IP (LTM): from 12.1.0 through 12.1.4; from 13.0.0 through 13.1.1.4; from 14.0.0 through 14.0.0.4; from 14.1.0 through 14.1.0.5
F5 Networks, Inc. BIG-IP (PEM): from 12.1.0 through 12.1.4; from 13.0.0 through 13.1.1.4; from 14.0.0 through 14.0.0.4; from 14.1.0 through 14.1.0.5
F5 Big-Ip Webaccelerator: from 12.1.0 through 12.1.4; from 13.0.0 through 13.1.1.4; from 14.0.0 through 14.0.0.4; from 14.1.0 through 14.1.0.5

How to fix

Upgrade to a fixed version: F5 BIG-IP DNS 14.0.0.4. Check the vendor advisory for mitigations.

References

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