{"schemaVersion":3,"id":"CVE-2025-40777","aliases":["ALPINE-CVE-2025-40777","SUSE-SU-2025:02349-1","UBUNTU-CVE-2025-40777","USN-7641-1","DEBIAN-CVE-2025-40777","CGA-f4wf-67mc-pqf6","CGA-xxhq-56rm-827h","openSUSE-SU-2025:15354-1"],"status":"published","duplicateOf":null,"title":null,"description":"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.\nThis 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 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