CVE-2022-3736: named configured to answer from stale cache may terminate unexpectedly while processing RRSIG queries
Document version: 2.0
Posting date: 25 January 2023
Program impacted: BIND 9
- 9.16.12 -> 9.16.36
- 9.18.0 -> 9.18.10
- 9.19.0 -> 9.19.8
BIND Supported Preview Edition
- 9.16.12-S1 -> 9.16.36-S1
(The flaw exists in the implementation of the
stale-answer-client-timeout option, which was first effectively introduced in BIND 9.16.12 and BIND 9.16.12-S1. That option is also configurable in BIND 9.11.33-S1 and newer BIND 9.11-S versions, but it is always replaced with 0 in all BIND 9.11.x-S1 releases.)
BIND 9 resolver can crash when stale cache and stale answers are enabled, option
stale-answer-client-timeout is set to a positive integer, and the resolver receives an RRSIG query.
By sending specific queries to the resolver, an attacker can cause
named to crash.
CVSS Score: 7.5
CVSS Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
For more information on the Common Vulnerability Scoring System and to obtain your specific environmental score please visit: https://nvd.nist.gov/vuln-metrics/cvss/v3-calculator?vector=AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H&version=3.1.
0 or to
off/disabled will prevent BIND from crashing due to this issue.
We are not aware of any active exploits.
Upgrade to the patched release most closely related to your current version of BIND 9:
BIND Supported Preview Edition is a special feature preview branch of BIND provided to eligible ISC support customers.
ISC would like to thank Borja Marcos from Sarenet (with assistance by Iratxe Niño from Fundación Sarenet) for bringing this vulnerability to our attention.
Document revision history:
- 1.0 Early Notification, 18 January 2023
- 2.0 Public disclosure, 25 January 2023
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 firstname.lastname@example.org. To report a new issue, please encrypt your message using email@example.com's PGP key, which can be found here: https://www.isc.org/pgpkey/. If you are unable to use encrypted email you may also report new issues at: https://www.isc.org/reportbug/.
ISC patches only currently supported versions. When possible we indicate EOL versions affected. For current information on which versions are actively supported, please see https://www.isc.org/download/.
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 https://kb.isc.org/docs/aa-00861.
The Knowledgebase article https://kb.isc.org/docs/cve-2022-3736 is the complete and official security advisory document.
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