Skip to content
CVE PROGRAM SOURCE RECORD5.3 Medium

CVE-2026-93007

Dnsmasq: dnsmasq: tcp/53 child-slot exhaustion starves dnssec validation

Description

A flaw was found in dnsmasq. The TCP DNS service uses a small fixed pool of child processes and does not set a receive timeout on client connections. A remote attacker can open idle TCP connections to port 53 and occupy the entire pool, preventing new TCP DNS connections and DNSSEC validation that requires TCP fallback. UDP DNS resolution continues, and occupied slots are released after a fixed lifetime.

Affected products

Version statuses are supplied by the assigning organization. Consult the original record for detailed ranges and platform conditions.

Red Hat Red Hat Ceph Storage 9

Default version status: affected

Red Hat Red Hat Enterprise Linux 10

Default version status: affected

Red Hat Red Hat Enterprise Linux 6

Default version status: affected

Red Hat Red Hat Enterprise Linux 7

Default version status: affected

Red Hat Red Hat Enterprise Linux 8

Default version status: affected

Red Hat Red Hat Enterprise Linux 9

Default version status: affected

Red Hat Red Hat OpenShift Container Platform 4

Default version status: affected

Red Hat Red Hat OpenShift Container Platform 4

Default version status: affected

Red Hat Red Hat OpenShift Container Platform 4

Default version status: affected

Red Hat Red Hat OpenShift Container Platform 4

Default version status: affected

Red Hat Red Hat OpenShift Container Platform 5

Default version status: affected

Red Hat Red Hat OpenShift Container Platform 5

Default version status: affected

Red Hat Red Hat OpenStack Platform 13 (Queens)

Default version status: affected

Red Hat Red Hat OpenStack Platform 18.0

Default version status: affected

References