cvedb.io
CVE-2025-40777
HIGH · CVSS 7.5
EPSS exploitation probability: 0%
Published 2025-07-16T18:15:24.770 · Last modified 2026-06-17T09:22:07.353

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.

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References

This product uses data from the NVD API but is not endorsed or certified by the NVD. Informational only; not professional security advice.