What is CVE-2025-40233?

CVE-2025-40233 is a unscored severity Linux kernel vulnerability, affecting Linux kernel versions from 3.0 onward and patched in 5.4.301, 5.10.246, 5.15.196 and others. CVE-2025-40233 has not been confirmed as actively exploited and is not listed in the CISA KEV catalog.

What is the CVSS score for CVE-2025-40233?

CVE-2025-40233 has a CVSS score of pending NVD analysis out of 10, rated awaiting scoring severity.

Is there a patch available for CVE-2025-40233?

Yes, CVE-2025-40233 has been patched. Fixed versions include 5.4.301, 5.10.246, 5.15.196 and others. If you are running Linux kernel 3.0 or later up to the fix versions, apply the relevant patch for your kernel branch.

Is CVE-2025-40233 actively exploited?

CVE-2025-40233 has not been confirmed as actively exploited and is not listed in the CISA KEV catalog.

CVE-2025-40233

In the Linux kernel, the following vulnerability has been resolved: ocfs2: clear extent cache after moving/defragmenting extents The extent map cache can become stale when extents are moved or defragmented, causing subsequent operations to see outdated extent flags. This triggers a BUG_ON in ocfs2_refcount_cal_cow_clusters(). The problem occurs when: 1. copy_file_range() creates a reflinked extent with OCFS2_EXT_REFCOUNTED 2. ioctl(FITRIM) triggers ocfs2_move_extents() 3. __ocfs2_move_extents_range() reads and caches the extent (flags=0x2) 4. ocfs2_move_extent()/ocfs2_defrag_extent() calls __ocfs2_move_extent() which clears OCFS2_EXT_REFCOUNTED flag on disk (flags=0x0) 5. The extent map cache is not invalidated after the move 6. Later write() operations read stale cached flags (0x2) but disk has updated flags (0x0), causing a mismatch 7. BUG_ON(!(rec->e_flags & OCFS2_EXT_REFCOUNTED)) triggers Fix by clearing the extent map cache after each extent move/defrag operation in __ocfs2_move_extents_range(). This ensures subsequent operations read fresh extent data from disk.

Package Linux Kernel

Published 2025-12-04

Last modified 2026-04-15

Patch available

Yes

Affected versions

Linux kernel versions 3.0 and later are affected. Fixed in 5.4.301, 5.10.246, 5.15.196, 6.1.158, 6.6.115, 6.12.56, 6.17.6, 6.18 and their respective stable series.

Affected from

≥ 3.0

Fixed in

✓ 5.4.301 5.4.x ✓ 5.10.246 5.10.x ✓ 5.15.196 5.15.x ✓ 6.1.158 6.1.x ✓ 6.6.115 6.6.x ✓ 6.12.56 6.12.x ✓ 6.17.6 6.17.x ✓ 6.18

References

The following references provide additional information about CVE-2025-40233 including vendor advisories, patch commits, exploit details, and third-party analysis. Links are sourced from the NIST NVD database.

Kernel patch commit
https://git.kernel.org/stable/c/78a63493f8e352296dbc7cb7b3f4973105e8679e
Patch
Kernel patch commit
https://git.kernel.org/stable/c/93166bc53c0e3587058327a4121daea34b4fecd5
Patch
Kernel patch commit
https://git.kernel.org/stable/c/93b1ab422f1966b71561158e1aedce4ec100f357
Patch

8 patch commits total View all on NVD

Frequently asked questions

What is CVE-2025-40233?

CVE-2025-40233 is a unscored severity Linux kernel vulnerability . It affects Linux kernel versions from 3.0 onward and has been patched in 5.4.301, 5.10.246, 5.15.196 and others. CVE-2025-40233 has not been confirmed as actively exploited and is not listed in the CISA KEV catalog.
Is there a patch available for CVE-2025-40233?

Yes — CVE-2025-40233 has been patched. Fixed versions include 5.4.301, 5.10.246, 5.15.196 and others. If you are running Linux kernel 3.0 or later up to the fix versions, apply the relevant patch for your kernel branch.
Is CVE-2025-40233 actively exploited?

No — CVE-2025-40233 has not been confirmed as actively exploited. It is not listed in the CISA Known Exploited Vulnerabilities (KEV) catalog.