SB2026110851 - Deadlock in Linux kernel smb server

Description

This security bulletin contains information about 1 vulnerability.

1) Deadlock (CVE-ID: CVE-2026-99280)

CWE-ID: CWE-833 - Deadlock

CVSSv4: 5.7 [CVSS:4.0/AV:L/AC:L/AT:P/PR:L/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N]

The vulnerability allows a local user to cause a denial of service.

The vulnerability exists due to a reference-lifetime race causing a deadlock in ksmbd session management when session registration fails or connection cleanup overlaps with per-session procfs reads. A local user can read a session's procfs entry during these operations to cause the final reference release to call proc_remove() from its own callback, which then waits for itself to finish and hangs.

Remediation

Install update from vendor's website.

References

• https://git.kernel.org/stable/c/1c087cf7d5386c708d8984b263280b42b3daada0
• https://git.kernel.org/stable/c/6789f0983f8e85ce3a5ed8c50fc05d613ead9c2c