CVE-2021-40083 Denial of service in n/a
A remote attacker can cause a denial of service in Knot Resolver by triggering an assertion failure via crafted NSEC3 records.
- Exploited in the wild
- Not known
- Login needed
- Not needed
- Attackable
- Over the internet
- Victim action needed
- Not needed
- Fix
- Available
What is CVE-2021-40083?
CVE-2021-40083 is a high-severity denial of service vulnerability in n/a, published on 25 Aug 2021. An attacker can exploit it over the internet without logging in, with no action from the victim.
Official description
Knot Resolver before 5.3.2 is prone to an assertion failure, triggerable by a remote attacker in an edge case (NSEC3 with too many iterations used for a positive wildcard proof).
Weakness: CWE-617
Which versions are affected by CVE-2021-40083?
It affects 1 product.
Products include Nic Knot Resolver.
How do I fix CVE-2021-40083?
Upgrade to a fixed version.
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-2021-40083 being exploited?
There is no known exploitation of CVE-2021-40083 in the wild and no public exploit code.
Other vulnerabilities in n/a
Sources
Also known as DEBIAN-CVE-2021-40083, GHSA-wvjr-27w9-ff2r.