VULNERABILITY INTELLIGENCE
CVE-2026-4408
CVSS score9 CRITICAL
EPSS probability2.50%
CISA KEVNot currently listed
Published2026-05-28
Last modified2026-10-26
CVSS vectorCVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:C/C:H/I:H/A:H
Description
A flaw was found in Samba. A remote attacker can exploit a misconfiguration in Samba file servers and classic domain controllers that use the "check password script" feature. If this script is configured with the %u substitution character, the client-controlled username is passed without proper escaping of shell meta-characters. This vulnerability allows an attacker to achieve remote command execution on the affected system. This issue primarily affects non-standard configurations where the "check password script" is used with %u and the samba-dcerpcd service is started as a system service.
Weakness classification
- secalert@redhat.com: CWE-78
- 0b0ca135-0b70-47e7-9f44-1890c2a1c46c: CWE-78