CVE-2026-64383
CriticalCVSS 9.8Exploitation Probability (EPSS)
Low risk37th percentile - higher than 37% of all known CVEs
Summary
In the Linux kernel, SMB client has a double-free vulnerability in SMB2_flush() replay. SMB2_flush() keeps response buffer bookkeeping across replay attempts. If a replayable flush response is received and the retry fails before storing a new response, flush_exit frees the stale pointer again. The fix reinitializes resp_buftype and rsp_iov at the top of the replay loop.
Risk Assessment
Double-free can cause memory corruption, system crashes, or potential exploitation for privilege escalation.
Recommendation
Update the Linux kernel to a version containing this fix to prevent double-free in SMB2_flush replay.
Original NVD description (English source)
In the Linux kernel, the following vulnerability has been resolved: smb: client: fix double-free in SMB2_flush() replay SMB2_flush() keeps its response buffer bookkeeping across replay attempts. If a replayable flush response is received and the retry then fails before cifs_send_recv() stores a replacement response, flush_exit will free the stale response pointer a second time. Reinitialize resp_buftype and rsp_iov at the top of the replay loop so cleanup only acts on response state produced by the current attempt. This fixes a double-free without changing replay handling for successful requests.