Skip to content
fr Sign in
7.5 High

CVE-2026-11721 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…

Description

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.

Affected products and versions

Product Affected versions Fixed in
BIND 9 9.21 9.21.0 → 9.21.23 No fix stated
BIND 9 9.20 9.20.0 → 9.20.24 No fix stated
BIND 9 9.11 9.11.0 → 9.18.50 No fix stated

References

Timeline

  1. Published
  2. Last modified

Other CVEs of BIND 9

The 87 CVEs of BIND 9 →
CVE-2026-97313 A recursive BIND server that receives a query with recursion desired (RD=1) followed by a non-recursive query (RD=0) may… 7.5 High CVE-2026-96888 A BIND resolver that is configured with both a "redirect" zone and "qname-minimization strict" may abort with an… 7.5 High CVE-2026-94300 Replaying GSS-TSIG signed UDP messages can result in memory corruption in "`named`" 8.1 High CVE-2026-19630 In a BIND resolver, inbound DNS protocol messages with a particular structure will result in additional processing, with… 7.5 High
Track this CVE