CVE-2026-72203

A flaw was found in the Linux kernel. This flaw involves a deadlock condition within the NTFS file system's writeback mechanism. Specifically, an ABBA deadlock can occur between the extent_lock and mrec_lock during inode and MFT (Master File Table) folio writeback operations. This could lead to a system hang or unresponsiveness, resulting in a Denial of Service (DoS).

A moderate-impact denial of service flaw was found in the Linux kernel NTFS file system's writeback mechanism. During concurrent writeback, the inode writeback path (ntfs_write_inode -> __ntfs_write_inode) acquires extent_lock and then mrec_lock, while the $MFT folio writeback path (ntfs_mft_writepages -> ntfs_write_mft_block) can hold an extent mrec_lock and try to acquire a base inode extent_lock, creating an ABBA deadlock. A local attacker with low privileges able to perform file operations on an NTFS file system could trigger this deadlock, causing the system to hang or become unresponsive, resulting in a denial of service that affects availability only (Red Hat CVSS 5.5, CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H). The issue occurs since upstream commit 6994acf33bae ("ntfs: use base mft_no when looking up base inode for extent record"). Red Hat Enterprise Linux and Red Hat In-Vehicle OS kernel and kernel-rt packages are not affected by this flaw because the vulnerable code is not present in these products. The upstream CVE record assigns a higher severity of 7.5 using a network attack vector, while Red Hat rates this issue as moderate because exploiting the deadlock requires local access to perform file operations on an NTFS file system.

The CVSS score(s) listed for this vulnerability do not reflect the associated product's status, and are included for informational purposes to better understand the severity of this vulnerability.