CVE-2021-25220 - CVE House
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Status published Medium CVE-2021-25220

DNS forwarders - cache poisoning vulnerability

Vulnerability Description

BIND 9.11.0 -> 9.11.36 9.12.0 -> 9.16.26 9.17.0 -> 9.18.0 BIND Supported Preview Editions: 9.11.4-S1 -> 9.11.36-S1 9.16.8-S1 -> 9.16.26-S1 Versions of BIND 9 earlier than those shown - back to 9.1.0, including Supported Preview Editions - are also believed to be affected but have not been tested as they are EOL. The cache could become poisoned with incorrect records leading to queries being made to the wrong servers, which might also result in false information being returned to clients.

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 Xiang Li, Baojun Liu, and Chaoyi Lu from Network and Information Security Lab, Tsinghua University and Changgen Zou from Qi An Xin Group Corp. for discovering and reporting this issue.

References

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Affected Vendor

Affected Software

BIND
Vulnerable Versions:
Open Source Branch 9.11 9.11.0 through versions before 9.11.37, Development Branch 9.17 BIND 9.17 all version, Open Source Branch 9.12-16 9.12.0 through versions before 9.16.27, Open Source Branch 9.18 9.18.0, Supported Preview Branch 9.11-S 9.11.0-S through versions before 9.11.37-S, Supported Preview Branch 9.16-S 9.16.0-S through versions before 9.16.27-S

Timeline

Official Publish: March 23rd, 2022
Last Modified: September 16th, 2024
Added to House: July 21st, 2026

CVSS Vectors

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

Weaknesses (CWE)

No CWE data available

MITRE ATT&CK TTPs

No associated TTPs found for this vulnerability.