CVE-2023-3866
HighCVSS 7.5Exploitation Probability (EPSS)
Very high risk95th percentile - higher than 95% of all known CVEs
Summary
In the Linux kernel, there is a vulnerability in ksmbd that involves missing validation of session ID and tree ID in compound requests. If the first operation in a compound request is SMB2 ECHO, validation is bypassed, which can lead to NULL pointer dereference and system crash.
Risk Assessment
The risk includes the possibility of system denial of service via specially crafted SMB2 requests, which could disrupt services.
Recommendation
It is recommended to update the Linux kernel to a version containing the fix for this vulnerability and monitor SMB2 traffic for suspicious requests.
Original NVD description (English source)
In the Linux kernel, the following vulnerability has been resolved: ksmbd: validate session id and tree id in the compound request This patch validate session id and tree id in compound request. If first operation in the compound is SMB2 ECHO request, ksmbd bypass session and tree validation. So work->sess and work->tcon could be NULL. If secound request in the compound access work->sess or tcon, It cause NULL pointer dereferecing error.