If a BIND resolver has cached a tree of SVCB/HTTPS AliasMode records, and is then queried for the root of that tree, the resolver will spend disproportionate CPU time constructing the response. This issue affects BIND 9 versions 9.18.0 through 9.18.50, 9.20.0 through 9.20.27, 9.21.0 through 9.21.25, 9.18.11-S1 through 9.18.50-S1, and 9.20.9-S1 through 9.20.27-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~ubuntu11:9.18.39-0ubuntu0.22.04.71:9.18.39-0ubuntu0.24.04.81:9.20.24-1ubuntu0.41:9.20.18-1ubuntu21:9.20.23-1ubuntu11:9.20.24-1ubuntu21:9.20.24-1ubuntu31:9.18.30-0ubuntu0.20.04.2+esm3Exploitability
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