Status: UPDATED | Advisory ID: CVE-2026-4408
| CVE | CVE-2026-4408 |
| CVSS Score / Version | 9.0 (Critical) / CVSS v3.1 |
| Updated | 2026-10-08 |
| CVSS Vector | CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:C/C:H/I:H/A:H |
| CVSS Prose | attack vector is network; attack complexity is high; privileges required is none; user interaction is none; scope is changed; confidentiality impact is high; integrity impact is high; availability impact is high. |
| Affected products | see table below |
| Classified as | CWE-78 (Improper Neutralization of Special Elements used in an OS Command ('OS Command Injection')) |
| Vendor | Product | Affected Versions | Patch Status |
|---|---|---|---|
| Red Hat | Enterprise Linux | ||
| Red Hat | OpenShift Container Platform | ||
| Red Hat | Red Hat Enterprise Linux 10 | ||
| Red Hat | Red Hat Enterprise Linux 10.0 Extended Update Support | ||
| Red Hat | Red Hat Enterprise Linux 8 | ||
| Red Hat | Red Hat Enterprise Linux 8.4 Advanced Mission Critical Update Support | ||
| Red Hat | Red Hat Enterprise Linux 8.4 Extended Update Support Long-Life Add-On | ||
| Red Hat | Red Hat Enterprise Linux 8.6 Advanced Mission Critical Update Support | ||
| Red Hat | Red Hat Enterprise Linux 8.6 Extended Update Support Long-Life Add-On | ||
| Red Hat | Red Hat Enterprise Linux 8.8 Telecommunications Update Service | ||
| Red Hat | Red Hat Enterprise Linux 8.8 Update Services for SAP Solutions | ||
| Red Hat | Red Hat Enterprise Linux 9 | ||
| Red Hat | Red Hat Enterprise Linux 9.2 Update Services for SAP Solutions | ||
| Red Hat | Red Hat Enterprise Linux 9.4 Update Services for SAP Solutions | ||
| Red Hat | Red Hat Enterprise Linux 9.6 Extended Update Support | ||
| Red Hat | Red Hat OpenShift Container Platform 4.12 | ||
| Red Hat | Red Hat OpenShift Container Platform 4.13 | ||
| Red Hat | Red Hat OpenShift Container Platform 4.14 | ||
| Red Hat | Red Hat OpenShift Container Platform 4.15 | ||
| Red Hat | Red Hat OpenShift Container Platform 4.16 | ||
| Red Hat | Red Hat OpenShift Container Platform 4.17 | ||
| Red Hat | Red Hat OpenShift Container Platform 4.18 | ||
| Red Hat | Red Hat OpenShift Container Platform 4.19 | ||
| Red Hat | Red Hat OpenShift Container Platform 4 | ||
| Red Hat | Red Hat OpenShift Container Platform 4.20 | ||
| Red Hat | Red Hat OpenShift Container Platform 4.21 | ||
| Red Hat | Red Hat Enterprise Linux 7 Extended Lifecycle Support |
| Subsystems | OT Supporting Infrastructure |
| Sectors | All Sectors |
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. (NVD)
Monitor Red Hat's web page for any future patch releases. See vendor advisory link below.
| Source | Reference |
|---|---|
| NVD | https://nvd.nist.gov/vuln/detail/CVE-2026-4408 |
| CVE | https://www.cve.org/CVERecord?id=CVE-2026-4408 |
| Vendor advisory | https://bugzilla.samba.org/show_bug.cgi?id=16034 |