CVE-2026-12244

Name of the Vulnerable Software and Affected Versions NSD (affected versions not specified)

Description A heap overflow occurs when NSD is configured as a secondary for a zone. A primary server can crash the system by sending an AXFR containing a DNS message with a specially crafted SVCB RR (Resource Record) with an rdata size of 65512. This causes a uint16 t variable used to allocate space for the RR wrap to overflow because the total size exceeds 65535. This allows an attacker to perform a controlled head write of up to 65509 bytes, potentially leading to remote code execution.

Recommendations At the moment, there is no information about a newer version that contains a fix for this vulnerability.