CVE-2026-81563

Summary

A BIND resolver encountering an SVCB/HTTPS AliasMode record referencing 14 or more SVCB/HTTPS ServiceMode records may fail to properly deallocate internal resources. If this happens repeatedly, resource exhaustion will eventually prevent the resolver from performing new recursive lookups. 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.

Affected Software

VendorProductVersion RangeStatus
ISCBIND 99.18.0 <= 9.18.50affected
ISCBIND 99.20.0 <= 9.20.27affected
ISCBIND 99.21.0 <= 9.21.25affected
ISCBIND 99.18.11-S1 <= 9.18.50-S1affected
ISCBIND 99.20.9-S1 <= 9.20.27-S1affected

Weaknesses

  • CWE-401: CWE-401 Missing Release of Memory after Effective Lifetime

Workarounds

No workarounds known.

References