CVE-2021-25215 - CVE House
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Status published High CVE-2021-25215

An assertion check can fail while answering queries for DNAME records that require the DNAME to be processed to resolve itself

Vulnerability Description

In BIND 9.0.0 -> 9.11.29, 9.12.0 -> 9.16.13, and versions BIND 9.9.3-S1 -> 9.11.29-S1 and 9.16.8-S1 -> 9.16.13-S1 of BIND Supported Preview Edition, as well as release versions 9.17.0 -> 9.17.11 of the BIND 9.17 development branch, when a vulnerable version of named receives a query for a record triggering the flaw described above, the named process will terminate due to a failed assertion check. The vulnerability affects all currently maintained BIND 9 branches (9.11, 9.11-S, 9.16, 9.16-S, 9.17) as well as all other versions of BIND 9.

Impact Analysis

Refer to official advisory for detailed impact metrics.

Remediation

Ensure systems are updated to the latest vendor-supplied patch levels.

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Credits & Attribution

The following person or organization is credited with identifying this vulnerability, as recorded in the NVD database:

  • ISC would like to thank Siva Kakarla for bringing this vulnerability to our attention.

References

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Affected Vendor

Affected Software

BIND9
Vulnerable Versions:
Open Source Branches 9.0 through 9.11 9.0.0 through versions before 9.11.30, Open Source Branches 9.12 through 9.16 9.12.0 through versions before 9.16.14, Supported Preview Branches 9.9-S through 9.11-S 9.9.3-S1 through versions before 9.11.30-S1, Supported Preview Branch 9.16-S 9.16.8-S1 through versions before 9.16.14-S1, Development Branch 9.17 9.17.0 through versiosn before 9.17.12

Timeline

Official Publish: April 29th, 2021
Last Modified: September 16th, 2024
Added to House: July 21st, 2026

CVSS Vectors

V3: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H

Weaknesses (CWE)

No CWE data available

MITRE ATT&CK TTPs

No associated TTPs found for this vulnerability.