SB20260424279 - Use-after-free in Linux kernel smb server
Published: April 24, 2026
Security Bulletin ID
SB20260424279
CSH Severity
Low
Patch available
YES
Number of vulnerabilities
1
Exploitation vector
Local access
Highest impact
Denial of service
Breakdown by Severity
- Low
- Medium
- High
- Critical
Description
This security bulletin contains information about 1 vulnerability.
1) Use-after-free (CVE-ID: CVE-2026-31444)
CWE-ID: CWE-416 - Use After Free
CVSSv4: 6.8 [CVSS:4.0/AV:L/AC:L/AT:N/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 use-after-free in smb_grant_oplock() when publishing oplock state to internal lists during concurrent access. A local user can trigger concurrent oplock operations to cause a denial of service.
The issue also involves a NULL pointer dereference in the same publication sequence.
Remediation
Install update from vendor's website.
References
- https://git.kernel.org/stable/c/48623ec358c1c600fa1e38368746f933e0f1a617
- https://git.kernel.org/stable/c/6d7e5a918c1d0aad06db0e17677b66fc9a471021
- https://git.kernel.org/stable/c/7de55bba69cbf0f9280daaea385daf08bc076121
- https://git.kernel.org/stable/c/9e785f004cbc56390479b77375726ea9b0d1a8a6
- https://git.kernel.org/stable/c/a5c6f6d6ceefed2d5210ee420fb75f8362461f46