Cyber Resilience

CVE-2021-40083

High

Published: 25 August 2021

Published
25 August 2021
Modified
21 November 2024
KEV Added
—
Patch
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CVSS Score v3.1 7.5 CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
EPSS Score 0.0084 75.2th percentile
Risk Priority 16 60% EPSS · 20% KEV · 20% CVSS

Summary

CVE-2021-40083 is a high-severity Reachable Assertion (CWE-617) vulnerability in Nic Knot Resolver. Its CVSS base score is 7.5 (High).

Operationally, ranked in the top 24.8% of CVEs by exploit likelihood; it is not currently listed in the CISA KEV catalog.

EU & UK References

Vulnerability details

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).

CWE(s)
CWE-617

Related Threats

No named actor attribution yet. ATT&CK technique mapping in progress for this CVE.

Affected Assets

nic
knot resolver
≤ 5.3.2

Mitigating Controls

No mitigating controls mapped yet. The per-CVE control annotator has not reached this CVE.

References