CVE-2026-72186
CriticalCVSS 9.1Exploitation Probability (EPSS)
Low risk9th percentile - higher than 9% of all known CVEs
Summary
In the Linux kernel's NTFS filesystem, system files such as $Bitmap can be written from userspace, leading to volume corruption and writeback deadlock. The fix marks base metadata files as immutable during inode read so the VFS rejects write, mmap, truncate, and unlink with -EPERM.
Risk Assessment
Writing to NTFS system files can corrupt the volume and cause system deadlock, leading to data loss and unavailability.
Recommendation
Apply the kernel update containing this fix to protect NTFS system files from userspace writes.
Original NVD description (English source)
In the Linux kernel, the following vulnerability has been resolved: ntfs: make system files immutable to prevent corruption When a system file such as $Bitmap is exposed via show_sys_files and written from userspace, the volume is corrupted and, because the cluster allocator scans $Bitmap through the same inode's page cache, a write to $Bitmap also deadlocks writeback against the folio it already holds locked. These files are maintained by the driver itself and have no valid reason to be written through the file interface. Mark base metadata files (mft_no < FILE_first_user) as immutable during inode read so the VFS rejects write, mmap, truncate and unlink with -EPERM. Directories are skipped so the root and $Extend remain usable. Internal metadata updates do not go through the VFS write path and are unaffected.