CVE-2026-53271

Name of the Vulnerable Software and Affected Versions Linux kernel (affected versions not specified)

Description A NULL-dereference issue exists in the ksmbd module. The functions smb2 oplock break noti() and smb2 lease break noti() read the opinfo->conn variable without using READ ONCE() or performing a NULL check. Because these functions execute after opinfo get list() releases the ci->m lock, a concurrent SMB2 LOGOFF operation via session fd check() can set op->conn to NULL. Subsequently, the function ksmbd conn r count inc(conn) attempts to write to a NULL pointer at offset 0xc4, which can be triggered remotely to cause a system oops (a kernel panic or crash).

Recommendations At the moment, there is no information about a newer version that contains a fix for this vulnerability.