CVE-2026-15779
mediumpriority · track · 0EPSS 0.001 · 4 %ileDEEUUSEPSS · scored 2026-10-27
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.
cvss
Technical severity, 0–10. One row per scoring source.
base score 0–10 · higher = more severe · hover a vector to decode
ssvc
A stakeholder decision — act, attend, or track — from exploitation and impact.
weaknesses
The CWE weakness classes this flaw belongs to.
affected products (4)
Products and version ranges known to be affected.
advisories (1)
Vendor and ecosystem advisories describing this.
- WID-SEC-W-2026-2376Samba: Schwachstelle ermöglicht Denial of ServiceDeutsch2026-07-15csaf · cert_bundDE
Ein lokaler Angreifer kann eine Schwachstelle in Samba ausnutzen, um einen Denial of Service Angriff durchzuführen.
also known as (3)
Other names and identifiers for this entity.
sources
Which sources assert this record, and when.
references (15)
External citations — patches, advisories, analysis.
- https://access.redhat.com/security/cve/CVE-2026-15779cnnvd
- https://bugzilla.redhat.com/show_bug.cgi?id=2499991cnnvd
- https://gitlab.com/samba-team/samba/-/blob/samba-4.19.4/nsswitch/pam_winbind.ccnnvd
- https://gitlab.com/samba-team/samba/-/blob/samba-4.23.5/nsswitch/pam_winbind.c#L1622cnnvd
- https://gitlab.com/samba-team/samba/-/blob/samba-4.24.3/nsswitch/pam_winbind.c#L1590cnnvd
- https://access.redhat.com/security/cve/CVE-2026-15779enisa_euvd
- https://bugzilla.redhat.com/show_bug.cgi?id=2499991enisa_euvd
- https://gitlab.com/samba-team/samba/-/blob/samba-4.19.4/nsswitch/pam_winbind.cenisa_euvd
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