CVE-2020-27721 Denial of service in BIG-IP GTM & DNS
Attackers can cause BIG-IP DNS to stop using LTM virtual servers for DNS responses, leading to service disruption in GSLB deployments.
- 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-2020-27721?
CVE-2020-27721 is a high-severity denial of service vulnerability in F5 Big-Ip Domain Name System, published on 24 Dec 2020. An attacker can exploit it over the internet without logging in, with no action from the victim.
Official description
In versions 16.0.0-16.0.0.1, 15.1.0-15.1.1, 14.1.0-14.1.3, 13.1.0-13.1.3.5, 12.1.0-12.1.5.2, and 11.6.1-11.6.5.2, in a BIG-IP DNS / BIG-IP LTM GSLB deployment, under certain circumstances, the BIG-IP DNS system may stop using a BIG-IP LTM virtual server for DNS response.
Which versions are affected by CVE-2020-27721?
It affects 2 products.
Products include F5 Big-Ip Domain Name System, F5 Big-Ip Global Traffic Manager.
How do I fix CVE-2020-27721?
No fix has been published for CVE-2020-27721 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-2020-27721 being exploited?
There is no known exploitation of CVE-2020-27721 in the wild and no public exploit code.
Other vulnerabilities in F5 Big-Ip Domain Name System
Sources
Also known as GHSA-7456-9w6m-v94r.