The issue is unexpected program termination based on ordering and/or specific content in responses to queries for CNAME or DNAME, and A records. Specifically, if a client queries for a DNAME and A record below the DNAME to the resolver, and the authoritative server responds positively to the A query but delays the DNAME response and later responds negatively, named may quit unexpectedly. Or, if a client queries for a CNAME and A record for the same name to the resolver, and the authoritative server responds positively to the A query but delays the CNAME response and later responds with a self-referential CNAME, the same failure may occur. This issue affects BIND 9 versions 9.18.0 through 9.18.50, 9.20.0 through 9.20.24, 9.18.11-S1 through 9.18.50-S1, and 9.20.9-S1 through 9.20.24-S1.
4.3.5-3ubuntu24.3.5-3ubuntu34.3.5-3ubuntu44.3.5-3ubuntu54.3.5-3ubuntu64.3.5-3ubuntu74.3.5-3ubuntu7.14.3.5-3ubuntu7.24.3.5-3ubuntu7.34.3.5-3ubuntu7.41:9.11.16+dfsg-3~build11:9.11.16+dfsg-3~ubuntu11:9.18.39-0ubuntu0.22.04.51:9.18.39-0ubuntu0.24.04.61:9.20.24-1ubuntu0.2Exploitability
AV:NAC:LPR:NUI:NScope
S:UImpact
C:NI:NA:HCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H