--- cve: "CVE-2026-4408" severity: "CRITICAL" cvss: 9.0 epss: "2.5%" vendor: "Red Hat" kev: false exploited: false published: "2026-05-28 09:16:47" tags: [cve, security, critical] source: tsecurity.de CVE-Dossier exported: "2026-09-02T21:37:27+02:00" --- # CVE-2026-4408 > 9.0 CRITICAL ## Beschreibung 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-Vektor ``` CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:C/C:H/I:H/A:H ``` | Metrik | Wert | Bewertung | |---|---|---| | AV Angriffsvektor | Netzwerk | bad | | AC Komplexität | Hoch | good | | PR Privilegien | Keine | bad | | UI Interaktion | Keine | bad | | S Scope | Verändert | bad | | C Vertraulichkeit | Hoch | bad | | I Integrität | Hoch | bad | | A Verfügbarkeit | Hoch | bad | ## Patch verfügbar (OSV) - 1c7d4b5b388ae2647732ed54834d5547a8c1357a (Commit) ## Referenzen - - - - - - - - - - - - - - - --- _Exportiert aus dem [tsecurity.de CVE-Dossier](https://tsecurity.de/cve?cve=CVE-2026-4408) · Datenquellen: EUVD (ENISA), NVD, OSV, CISA KEV, FIRST EPSS, Exploit-DB, BSI BITS_