CVE-2026-81563 SVCB AliasMode additional-data error leaks qpcache references

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...

CVE-2026-81563

CVE-2026-81563 is a resource exhaustion vulnerability in the BIND 9 resolver (ISC). When a resolver encounters an SVCB/HTTPS AliasMode record referencing 14 or more SVCB/HTTPS ServiceMode records , it may fail to properly deallocate internal qpcache references . Repeated occurrences lead to resou...