CVE-2019-6611 Denial of service in BIG-IP (LTM, AAM, AFM, Analytics, APM, ASM, DNS, Edge Gateway, FPS, GTM, Link Controller, PEM, WebAccelerator)

High 7.5 Published 3 May 2019 Updated 4 Aug 2024

Attackers can cause a denial of service by sending rare PPTP traffic sequences to BIG-IP systems configured with CGNAT and PPTP profiles.

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-2019-6611?

CVE-2019-6611 is a high-severity denial of service vulnerability in F5 Big-Ip Access Policy Manager, published on 3 May 2019. An attacker can exploit it over the internet without logging in, with no action from the victim.

Official description

When BIG-IP 14.0.0-14.1.0.1, 13.0.0-13.1.1.4, 12.1.0-12.1.4, 11.6.1-11.6.3.4, and 11.5.2-11.5.8 are processing certain rare data sequences occurring in PPTP VPN traffic, the BIG-IP system may execute incorrect logic. The TMM may restart and produce a core file as a result of this condition. The BIG-IP system provisioned with the CGNAT module and configured with a virtual server using a PPTP profile is exposed to this vulnerability.

Which versions are affected by CVE-2019-6611?

It affects 13 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 7 more.

How do I fix CVE-2019-6611?

No fix has been published for CVE-2019-6611 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-2019-6611 being exploited?

There is no known exploitation of CVE-2019-6611 in the wild and no public exploit code.

All F5 Big-Ip Access Policy Manager vulnerabilities

Sources

Also known as GHSA-cm77-cg9p-x2w6.