Bugzilla – Bug 1197138
VUL-0: CVE-2022-0667: bind: possible assertion failure when backstop lifetime timer has timed out
Last modified: 2022-03-29 12:25:08 UTC
Date: Tue, 15 Mar 2022 13:38:28 +0000
From: ISC Security Officer <email@example.com>
Document version: 1.0
Posting date: 16 March 2022
Program impacted: BIND
Versions affected: BIND 9.18.0
In BIND 9.18.0 the recursive client code was refactored. This refactoring
introduced a "backstop lifetime timer."
While BIND is processing a request for a DS record that needs to be
forwarded, it waits until this processing is complete or until the
backstop lifetime timer has timed out. When the resume_dslookup() function
is called as a result of such a timeout, the function does not test
whether the fetch has previously been shut down. This introduces the
possibility of triggering an assertion failure, which could cause the BIND
process to terminate.
Only the BIND 9.18 branch is affected.
When the vulnerability is triggered the BIND process will exit.
CVSS Score: 7.0
CVSS Vector: CVSS:3.1:AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H/E:F/RL:O/RC:C
For more information on the Common Vulnerability Scoring System and to
obtain your specific environmental score, please visit:
No workarounds known.
We are not aware of any active exploits.
Users of BIND 9.18.0 should upgrade to BIND 9.18.1
Document revision history:
1.0 Early Notification, 9 March 2022
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 go
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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
This Knowledgebase article https://kb.isc.org/docs/cve-2022-0667 is the
complete and official security advisory document.
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Created attachment 857004 [details]
This bug applies only to factory, fixed with upgrade to 9.18.1: