DEBIAN-CVE-2026-4408

Advisory lineage Upstream: 1 Downstream: 0
Upstream
CVE-2026-4408
Published: 28 May 2026, 09:16
Last modified:21 Jul 2026, 11:15

Vulnerability Summary

Overall Risk (default)
high
70/100
CVSS Score
9.8 CRITICAL
3.1 (osv_debian)
EPSS Score
No data
KEV
Not listed
Ransomware
No reports
Public exploits
None found
Dark Web
Not detected

Timeline

28 May 2026, 09:16
Published
Vulnerability first disclosed
21 Jul 2026, 11:15
Last Modified
Vulnerability information updated

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 Metrics

  • v3.1•CRITICAL•Score: 9.8CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H

Affected Systems

  • debian•samba

    all | all | < 2:4.13.13+dfsg-1~deb11u8 | < 2:4.17.12+dfsg-0+deb12u4 | < 2:4.22.8+dfsg-0+deb13u2 | < 2:4.24.3+dfsg-1

References (1)