CVE-2024-50086
CriticalCVSS 9.8Exploitation Probability (EPSS)
Low risk11th percentile - higher than 11% of all known CVEs
Summary
In the Linux kernel, the ksmbd module has a use-after-free (UAF) issue during SMB2 session log off. There is a race between session log off and session setup, leading to UAF. The fix adds session lock when setting SMB2_SESSION_EXPIRED and reference count to session struct to prevent freeing while in use.
Risk Assessment
An attacker could exploit the race to cause a system crash or potentially execute arbitrary code in kernel context, leading to full system compromise.
Recommendation
Immediately update the Linux kernel to a version containing the fix for CVE-2024-50086. Monitor vendor distributions for patches.
Original NVD description (English source)
In the Linux kernel, the following vulnerability has been resolved: ksmbd: fix user-after-free from session log off There is racy issue between smb2 session log off and smb2 session setup. It will cause user-after-free from session log off. This add session_lock when setting SMB2_SESSION_EXPIRED and referece count to session struct not to free session while it is being used.