CVE-2026-93011 Dnsmasq: dnsmasq: heap out-of-bounds write in dnssec validator via to_wire/from_wire transforms

Description

A flaw was found in dnsmasq. After a reduction of internal domain-name buffer sizes, the DNSSEC validator can write a few bytes past a name buffer when converting names to and from DNS wire format. An attacker who can cause the server to validate a crafted DNSSEC response may overwrite a small amount of adjacent heap metadata. DNSSEC support is not compiled in by default and must also be enabled at runtime.

Exploitable remotely over the network, without an account and without any user action; the impact on data or service is limited.

Attack vector

Network

Attack complexity

Low

Privileges required

None

Interaction

None

Scope

Unchanged

Confidentiality

None

Integrity

Low

Availability

None

Affected products and versions