CVE-2026-15779 MEDIUM

CVE-2026-15779: Samba-winbind: samba: pam_winbind mkhomedir chowns critical system paths without validation

Vendor Red Hat
Product Red Hat Enterprise Linux 10
Weakness CWE-732
Published July 15, 2026
Last update July 15, 2026

CVSS base score

6.1/10
Attack vector Local
Attack complexity Low
Privileges required Low
User interaction None
Confidentiality None
Integrity Low

CVSS vector

CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:L/A:H

What the vulnerability does

01Description

A flaw was found in samba's pam_winbind. When mkhomedir is enabled, pam_winbind chowns the target account's home directory without validating the path is not a critical system directory such as /. On affected systems, accounts with / as their home directory (a common default for system accounts) can have this triggered not only by root, but by a non-root user holding a narrow sudo delegation to run commands as that account, causing ownership of / to change and resulting in severe denial of service (SSH, sudo, and package-manager failures). The change does not grant write access to / (which ships with restrictive 0555 permissions on RHEL), so the impact is availability loss rather than further privilege escalation.

Key dates

02Disclosure timeline

July 15, 2026 CVE published
July 15, 2026 Record updated