CVE-2021-40083

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).

Category

7.5
CVSS
Severity: High
CVSS 3.1 •
CVSS 2.0 •
EPSS 0.27%
Third-Party Advisory nic.cz
Affected: n/a n/a
Published at:
Updated at:

References

Link Tags
https://gitlab.nic.cz/knot/knot-resolver/-/merge_requests/1169 third party advisory patch

Frequently Asked Questions

What is the severity of CVE-2021-40083?
CVE-2021-40083 has been scored as a high severity vulnerability.
How to fix CVE-2021-40083?
To fix CVE-2021-40083, make sure you are using an up-to-date version of the affected component(s) by checking the vendor release notes. As for now, there are no other specific guidelines available.
Is CVE-2021-40083 being actively exploited in the wild?
As for now, there are no information to confirm that CVE-2021-40083 is being actively exploited. According to its EPSS score, there is a ~0% probability that this vulnerability will be exploited by malicious actors in the next 30 days.
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