Samba: remote code execution in samr_CVE-2026-4408

9 / 10

CRITICAL

CVSS: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.

AI Analysis

Remote code execution vulnerability in Samba due to misconfiguration in the 'check password script' feature

Basic Information

ID CVE-2026-4408

Source redhat

Published May 28, 2026 at 07:25

Affected Product

Vendor Red Hat

Product Red Hat Enterprise Linux 10

CWE Classification

CWE-78

AI Assessment

AI Score 9 / 10

AI Severity Critical

Vendor Samba

Product Samba

Version Affected versions not specified

References

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    "published": "2026-05-28T07:25:27.169Z",
    "modified": "2026-05-28T07:25:27.169Z",
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