CVE-2026-81736

Description

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.

CVSS Vector

References

• https://downloads.isc.org/isc/bind9/9.20.29
• https://downloads.isc.org/isc/bind9/9.21.26
• https://kb.isc.org/docs/cve-2026-81736