CVE-2023-2911: Exceeding the recursive-clients quota may cause named to terminate unexpectedly when stale-answer-client-timeout is set to 0
If the recursive-clients quota is reached on a BIND 9 resolver configured with both stale-answer-enable yes; and stale-answer-client-timeout 0;, a sequence of serve-stale-related lookups could cause named to loop and terminate unexpectedly due to a stack overflow. This issue affects BIND 9 versions 9.16.33 through 9.16.41, 9.18.7 through 9.18.15, 9.16.33-S1 through 9.16.41-S1, and 9.18.11-S1 through 9.18.15-S1.
Affected Software
Remediation
Patch Available
Information
Event History
Frequently Asked Questions
What is CVE-2023-2911?
CVE-2023-2911 is a vulnerability that affects BIND 9 resolvers configured with both `stale-answer-enable yes;` and `stale-answer-client-timeout 0;`.
How does CVE-2023-2911 affect BIND 9?
CVE-2023-2911 can cause `named` to loop and terminate unexpectedly due to a stack overflow if the `recursive-clients` quota is reached.
Which versions of BIND 9 are affected by CVE-2023-2911?
BIND 9 versions 9.16.1-0ubuntu2.15, 9.18.12-0ubuntu0.22.04.2, 9.18.12-0ubuntu0.22.10.2, 9.18.12-1ubuntu1.1, 9.16.42, 9.18.16, 9.11.5.P4+dfsg-5.1+deb10u7, 9.11.5.P4+dfsg-5.1+deb10u9, 9.16.44-1~deb11u1, 9.18.16-1~deb12u1, 9.18.19-1~deb12u1, and 9.19.17 are affected.
What is the severity of CVE-2023-2911?
The severity of CVE-2023-2911 is not specified in the provided information.
How do I fix CVE-2023-2911?
To fix CVE-2023-2911, update BIND 9 to a version that includes the necessary security patch.
Where can I find more information about CVE-2023-2911?
You can find more information about CVE-2023-2911 at the following references: - [ISC Knowledge Base](https://kb.isc.org/docs/cve-2023-2911) - [Openwall Mailing List](http://www.openwall.com/lists/oss-security/2023/06/21/6) - [Fedora Project Package Announce Mailing List](https://lists.fedoraproject.org/archives/list/package-announce@lists.fedoraproject.org/message/U3K6AJK7RRSR53HRF5GGKPA6PDUDWOD2/)