It is possible for an attacker's zone to respond to a query with an RRSIG that has a smaller number of labels than the zone in which the RRSIG is contained. This causes named to produce a wildcard name for a zone that is shorter than the attacker's zone, which can result in cache poisoning. For this attack to have any effect, the resolver under attack must have set synth-from-dnssec yes; (which is the default). This issue affects BIND 9 versions 9.11.0 through 9.18.50, 9.20.0 through 9.20.24, 9.21.0 through 9.21.23, 9.11.3-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:HA:NCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:H/A:N