CVE-2025-40777 (GCVE-0-2025-40777)
Vulnerability from cvelistv5
Published
2025-07-16 17:38
Modified
2025-11-04 21:10
Severity ?
7.5 (High) - CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
CWE
Summary
If a `named` caching resolver is configured with `serve-stale-enable` `yes`, and with `stale-answer-client-timeout` set to `0` (the only allowable value other than `disabled`), and if the resolver, in the process of resolving a query, encounters a CNAME chain involving a specific combination of cached or authoritative records, the daemon will abort with an assertion failure. This issue affects BIND 9 versions 9.20.0 through 9.20.10, 9.21.0 through 9.21.9, and 9.20.9-S1 through 9.20.10-S1.
References
Impacted products
Vendor Product Version
ISC BIND 9 Version: 9.20.0   <
Version: 9.21.0   <
Version: 9.20.9-S1   <
Patch: 9.18.0
Patch: 9.18.11-S1
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