SB2026091946 - Out-of-bounds read in Linux kernel smb server
Published: September 19, 2026
Security Bulletin ID
SB2026091946
CSH Severity
Low
Patch available
YES
Number of vulnerabilities
1
Exploitation vector
Local access
Highest impact
Information disclosure
Breakdown by Severity
- Low
- Medium
- High
- Critical
Description
This security bulletin contains information about 1 vulnerability.
1) Out-of-bounds read (CVE-ID: CVE-2026-90170)
CWE-ID: CWE-125 - Out-of-bounds read
CVSSv4: 4.8 [CVSS:4.0/AV:L/AC:L/AT:N/PR:L/UI:N/VC:L/VI:N/VA:N/SC:N/SI:N/SA:N]
The vulnerability allows a local user to read memory out of bounds.
The vulnerability exists due to an out-of-bounds read in the ksmbd ipc_validate_msg() function when processing undersized IPC responses supplied by the userspace ksmbd daemon. A local user can provide a short IPC response to read memory out of bounds.
The issue is reachable for KSMBD_EVENT_RPC_REQUEST messages.
Remediation
Install update from vendor's website.
References
- https://git.kernel.org/stable/c/0aa8f94bfd4d818284c8a7ce0040d40ca1ec3595
- https://git.kernel.org/stable/c/17b7d1a2b4d5473df5dca8c9a07d65021806c23a
- https://git.kernel.org/stable/c/398cba4b646a6c08ff3d79e6b1e70e5ddae8a065
- https://git.kernel.org/stable/c/c494fcf8e89e3c970e13d78ebe62bf5d8f2b1c52
- https://git.kernel.org/stable/c/e9b33376bd07bca4175f7bcc2d6034ef250f8181