CVE-2026-4408
CRITICAL EPSS 82.7%
Published May 28, 20261mo ago · Modified Jun 17, 20261w ago
9.8 CVSS 3.1
Published May 28, 2026 1mo ago
Last Modified Jun 17, 2026 1w ago
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.
CVSS Details
Base Score
Exploitability
Impact
Vector string
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H Attack Vector Network
Attack Complexity Low
Privileges Required None
User Interaction None
Scope Unchanged
Confidentiality High
Integrity High
Availability High
Threat Intelligence
EPSS Exploit Probability
82.7% percentile
Exploit & Patch Status
No Known Exploit
No Patch Available
Weaknesses 1
CWE-78 OS Command Injection Injection
Affected Products 5
References 7
- access.redhat.com https://access.redhat.com/errata/RHSA-2026:22644
- access.redhat.com https://access.redhat.com/errata/RHSA-2026:22963
- access.redhat.com https://access.redhat.com/errata/RHSA-2026:25049
- access.redhat.com https://access.redhat.com/errata/RHSA-2026:25979
- access.redhat.com https://access.redhat.com/security/cve/CVE-2026-4408
- bugzilla.redhat.com https://bugzilla.redhat.com/show_bug.cgi?id=2479762
- bugzilla.samba.org https://bugzilla.samba.org/show_bug.cgi?id=16034
Remediation
No remediation data recorded yet
Check vendor advisories and the NVD entry for patch availability.