CVE-2026-81563

A flaw was found in the BIND resolver. A remote attacker could exploit a vulnerability in the processing of SVCB/HTTPS AliasMode records that reference numerous ServiceMode records. This could lead to the resolver failing to properly release internal resources, causing resource exhaustion. Repeated exploitation would prevent the resolver from performing new recursive lookups, resulting in a Denial of Service (DoS).

This Important denial of service vulnerability affects BIND resolvers, which are critical for DNS resolution in Red Hat environments. Repeated processing of specially crafted SVCB/HTTPS AliasMode records can exhaust internal resources, ultimately preventing the resolver from performing new recursive lookups and disrupting service availability.

The CVSS score(s) listed for this vulnerability do not reflect the associated product's status, and are included for informational purposes to better understand the severity of this vulnerability.

Mitigation for this issue is either not available or the currently available options do not meet the Red Hat Product Security criteria comprising ease of use and deployment, applicability to widespread installation base, or stability.