SB20261007190 - Use-after-free in Linux kernel smb client
Published: October 7, 2026
Security Bulletin ID
SB20261007190
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-2026-98175)
CWE-ID: CWE-416 - Use After Free
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 use-after-free in the SMB client clean_demultiplex_info() function when the demultiplex thread exits while server reconnect work remains queued. A local user can trigger this cleanup sequence to cause a denial of service.
The queued smb2_reconnect_server() work subsequently reads the srv_count field of the freed server structure.
Remediation
Install update from vendor's website.
References
- https://git.kernel.org/stable/c/180380272f116dbd2b0354c5c7872e112e519149
- https://git.kernel.org/stable/c/2e5103e11a17c274715dd56cf185eeedccf686b8
- https://git.kernel.org/stable/c/7ab9ceedd860216fb97f2d8574cbe58b8906f42a
- https://git.kernel.org/stable/c/c65eae6f61d1778ff7a82e4aae4080e26f486af1
- https://git.kernel.org/stable/c/e3f6a779433d13aafb5edab59e4f9313051e8a52