CVE-2019-6684 Denial of service in BIG-IP

High 7.5 Published 23 Dec 2019 Updated 4 Aug 2024

Attackers can cause denial of service in F5 BIG-IP vCMP environments by exploiting fragmented broadcast packet handling issues.

Exploited in the wild: Not known
Login needed: Not needed
Attackable: Over the internet
Victim action needed: Not needed
Fix: None listed

What is CVE-2019-6684?

CVE-2019-6684 is a high-severity denial of service vulnerability in F5 Big-Ip Access Policy Manager, published on 23 Dec 2019. An attacker can exploit it over the internet without logging in, with no action from the victim.

Official description

On versions 15.0.0-15.0.1.1, 14.0.0-14.1.2.2, 13.1.0-13.1.3.1, 12.1.0-12.1.5, and 11.5.2-11.6.5.1, under certain conditions, a multi-bladed BIG-IP Virtual Clustered Multiprocessing (vCMP) may drop broadcast packets when they are rebroadcast to the vCMP guest secondary blades. An attacker can leverage the fragmented broadcast IP packets to perform any type of fragmentation-based attack.

Which versions are affected by CVE-2019-6684?

It affects 11 products.

Products include F5 Big-Ip Access Policy Manager, F5 Big-Ip Advanced Firewall Manager, F5 Big-Ip Analytics, F5 Big-Ip Application Acceleration Manager, F5 Big-Ip Application Security Manager, F5 Big-Ip Domain Name System and 5 more.

How do I fix CVE-2019-6684?

No fix has been published for CVE-2019-6684 yet. Limit exposure of the affected software until one is available.

Upgrade, then put limits on request size, rate and nesting depth so one client cannot exhaust the service. More about Denial of service.

Is CVE-2019-6684 being exploited?

There is no known exploitation of CVE-2019-6684 in the wild and no public exploit code.

All F5 Big-Ip Access Policy Manager vulnerabilities

Sources

Also known as GHSA-2r69-jgh4-vvpm.