CVE-2026-3238: Samba: denial of service against ad dc wins server

Severity: high (CVSS 7.5 v3.1)
Exploited in the wild: not listed in CISA KEV
EPSS: 2.7% probability of exploitation in the next 30 days
Public exploit or detection template: none known
Published: 2026-06-08 · updated 2026-09-01
Weakness: CWE-476

Description

A flaw was found in Samba’s WINS server component when running as an Active Directory Domain Controller. The WINS protocol handlers for certain request types did not properly validate incoming packets, allowing an unauthenticated remote attacker to trigger a NULL pointer dereference and crash the WINS service using specially crafted UDP packets.

Affected products

Red Hat OpenShift Container Platform 4.18: all versions

References

https://access.redhat.com/security/cve/CVE-2026-3238
https://bugzilla.redhat.com/show_bug.cgi?id=2486176
https://www.samba.org/samba/security/CVE-2026-3238.html
https://access.redhat.com/security/cve/CVE-2026-3238
https://bugzilla.redhat.com/show_bug.cgi?id=2486176
https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-3238.json

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