CVE-2025-39943
CriticalCVSS 9.4Exploitation Probability (EPSS)
Low risk16th percentile - higher than 16% of all known CVEs
Summary
In the Linux kernel, a vulnerability was found in the ksmbd module (SMB server) in SMBDirect data transfer handling. Invalid data_offset and data_length fields in the smb_direct_data_transfer structure can lead to out-of-bounds memory access.
Risk Assessment
An attacker can send a crafted SMB request, causing kernel memory corruption, potentially leading to system crashes or privilege escalation.
Recommendation
Apply the kernel patch that fixes CVE-2025-39943. Update your system to the latest stable kernel version.
Original NVD description (English source)
In the Linux kernel, the following vulnerability has been resolved: ksmbd: smbdirect: validate data_offset and data_length field of smb_direct_data_transfer If data_offset and data_length of smb_direct_data_transfer struct are invalid, out of bounds issue could happen. This patch validate data_offset and data_length field in recv_done.