CVE-2021-40083: High severity nic Knot Resolver vulnerability

Published Aug 25, 2021
·
Updated

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).

Affected Software

1 affected component
nic Knot Resolver<5.3.2

Remediation

Recommended actions to resolve this vulnerability, in priority order.

  1. Upgrade

    Upgrade Knot Resolver to a version that resolves this vulnerability.

    Fixed in 5.3.2

Event History

Aug 25, 2021
CVE Published
via MITRE·12:21 AM
Data Sourced
via MITRE·12:21 AM
Description
Data Sourced
via NVD·01:15 AM
RemedyDescriptionSeverityWeaknessAffected Software
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Frequently Asked Questions

1

What is CVE-2021-40083?

CVE-2021-40083 is a vulnerability in Knot Resolver before version 5.3.2 that can be triggered by a remote attacker in an edge case.

2

How severe is CVE-2021-40083?

CVE-2021-40083 has a severity rating of 7.5, which is considered high.

3

What is the affected software for CVE-2021-40083?

The affected software for CVE-2021-40083 is Knot Resolver before version 5.3.2.

4

How can CVE-2021-40083 be triggered?

CVE-2021-40083 can be triggered by a remote attacker in an edge case involving NSEC3 with too many iterations used for a positive wildcard proof.

5

Is there a fix for CVE-2021-40083?

Yes, the fix for CVE-2021-40083 is available in Knot Resolver version 5.3.2.

Contact

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