CVE-2026-15779 (GCVE-0-2026-15779)

Vulnerability from cvelistv5 – Published: 2026-07-15 12:33 – Updated: 2026-07-15 13:04
VLAI
Title
Samba-winbind: samba: pam_winbind mkhomedir chowns critical system paths without validation
Summary
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.
Severity
6.1 (Medium)
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:L/A:H
SSVC
Exploitation: none Automatable: no Technical Impact: partial
CISA Coordinator · CISA-ADP (v2.0.3)
Decision recorded 2026-07-15 13:04 UTC
CWE
  • CWE-732 - Incorrect Permission Assignment for Critical Resource
Assigner
References
Impacted products
Date Public
2026-07-14 00:00
Credits
This issue was discovered by Runar Lundgren (Red Hat).
Show details on NVD website
To clipboard 

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