SB2025103126 - Improper locking in Linux kernel smb server
Published: October 31, 2025
Security Bulletin ID
SB2025103126
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) Improper locking (CVE-ID: CVE-2025-40090)
CWE-ID: CWE-667 - Improper Locking
CVSSv4: 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/E:U/U:Clear
The vulnerability allows a local user to perform a denial of service (DoS) attack.
The vulnerability exists due to improper locking within the ksmbd_rpc_write(), ksmbd_rpc_read() and ksmbd_rpc_ioctl() functions in fs/smb/server/transport_ipc.c. A local user can perform a denial of service (DoS) attack.
Remediation
Install update from vendor's website.