CVE-2022-3080: BIND 9 resolvers configured to answer from stale cache with zero stale-answer-client-timeout may terminate unexpectedly
  • 21 Sep 2022
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CVE-2022-3080: BIND 9 resolvers configured to answer from stale cache with zero stale-answer-client-timeout may terminate unexpectedly

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Article Summary

CVE: CVE-2022-3080

Document version: 2.0

Posting date: 21 September 2022

Program impacted: BIND

Versions affected:


  • 9.16.14 -> 9.16.32
  • 9.18.0 -> 9.18.6
  • 9.19.0 -> 9.19.4

BIND Supported Preview Edition

  • 9.16.14-S1 -> 9.16.32-S1 (Note that no versions of the BIND 9.11 Supported Preview Edition are vulnerable).

Severity: High

Exploitable: Remotely


BIND 9 resolver can crash when stale cache and stale answers are enabled, option stale-answer-client-timeout is set to 0 and there is a stale CNAME in the cache for an incoming query.


By sending specific queries to the resolver, an attacker can cause named to crash.

CVSS Score: 7.5


For more information on the Common Vulnerability Scoring System and to obtain your specific environmental score please visit:


Setting stale-answer-client-timeout to off or to an integer greater than 0 will prevent BIND from crashing due to this issue.

Active exploits:

We are not aware of any active exploits.


Upgrade to the patched release most closely related to your current version of BIND:

  • 9.16.33
  • 9.18.7
  • 9.19.5

BIND Supported Preview Edition is a special feature preview branch of BIND provided to eligible ISC support customers.

  • 9.16.33-S1


ISC would like to thank Maksym Odinintsev for bringing this vulnerability to our attention.

Document revision history:

1.0 Early Notification, 14 September 2022
1.1 Minor punctuation corrections, 19 September 2022
1.2 Fixed the option name used in the CVE title, 21 September 2022
2.0 Public disclosure, 21 September 2022

Related documents:

See our BIND 9 Security Vulnerability Matrix for a complete listing of security vulnerabilities and versions affected.

Do you still have questions? Questions regarding this advisory should be mailed to To report a new issue, please encrypt your message using's PGP key, which can be found here: If you are unable to use encrypted email you may also report new issues at:


ISC patches only currently supported versions. When possible we indicate EOL versions affected. For current information on which versions are actively supported, please see

ISC Security Vulnerability Disclosure Policy:

Details of our current security advisory policy and practice can be found in the ISC Software Defect and Security Vulnerability Disclosure Policy at

The Knowledgebase article is the complete and official security advisory document.

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