CVE-2026-4408 (GCVE-0-2026-4408)
Vulnerability from cvelistv5
Published
2026-05-28 07:25
Modified
2026-06-08 15:40
Severity ?
9.0 (Critical) - CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:C/C:H/I:H/A:H
CWE
  • CWE-78 - Improper Neutralization of Special Elements used in an OS Command ('OS Command Injection')
Summary
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.
References
Impacted products
Vendor Product Version
Red Hat Red Hat Enterprise Linux 10 Unaffected: 0:4.23.5-109.el10_2   < *
    cpe:/o:redhat:enterprise_linux:10.2
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   Red Hat Red Hat Enterprise Linux 8 Unaffected: 0:4.19.4-16.el8_10   < *
    cpe:/a:redhat:enterprise_linux:8::appstream
    cpe:/a:redhat:enterprise_linux:8::crb
    cpe:/o:redhat:enterprise_linux:8::baseos
 Create a notification for this product.
   Red Hat Red Hat Enterprise Linux 8 Unaffected: 0:4.19.4-16.el8_10   < *
    cpe:/a:redhat:enterprise_linux:8::appstream
    cpe:/a:redhat:enterprise_linux:8::crb
    cpe:/o:redhat:enterprise_linux:8::baseos
 Create a notification for this product.
   Red Hat Red Hat Enterprise Linux 6     cpe:/o:redhat:enterprise_linux:6
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   Red Hat Red Hat Enterprise Linux 6     cpe:/o:redhat:enterprise_linux:6
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   Red Hat Red Hat Enterprise Linux 7     cpe:/o:redhat:enterprise_linux:7
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   Red Hat Red Hat Enterprise Linux 9     cpe:/o:redhat:enterprise_linux:9
 Create a notification for this product.
   Red Hat Red Hat OpenShift Container Platform 4     cpe:/a:redhat:openshift:4
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