CVE-2026-90418

Description

In the Linux kernel, the following vulnerability has been resolved: nilfs2: fix BUG in nilfs_copy_dirty_pages() on dirty state mismatch Syzbot reported a kernel BUG triggered within nilfs_copy_dirty_pages(), which copies dirty DAT file folios/pages to its shadow page cache. The BUG occurs when a retrieved dirty folio/page unexpectedly loses its 'dirty' status. This issue arises because, since the commit referenced below, the 'dirty' flag of a folio/page can be cleared asynchronously after the filesystem detects metadata corruption and transitions to read-only mode. Resolve the issue by returning an -EROFS error if the filesystem has transitioned to read-only mode. Also change the behavior to issue a kernel warning only once instead of triggering a kernel BUG when this unexpected 'dirty' state is detected while the filesystem is not in read-only mode.

Is your site exposed to CVE-2026-90418?

Run a free security scan — no signup, results in seconds.

EPSS — Exploit Prediction

0.0017

Probability of exploitation

0.06%

Percentile rank

EPSS estimates the probability that this vulnerability will be exploited in the wild within the next 30 days. A higher score means more likely to be exploited.

References

Other References

https://git.kernel.org/stable/c/3904fb0ee741ebbbc27ec8f50a9bb6cd31e8af05 https://git.kernel.org/stable/c/4e1f21e7540b25d83f86b50780836ed7d2afcc93 https://git.kernel.org/stable/c/5166a21b12f549774f2983fa86d2526ea9e66ace https://git.kernel.org/stable/c/66f4ad3ce158902e5f98afea93189972ed8750c2 https://git.kernel.org/stable/c/f181155baf0c93a74ebe804c6cecbe970e78ee9e

Frequently Asked Questions

What is CVE-2026-90418? +

In the Linux kernel, the following vulnerability has been resolved: nilfs2: fix BUG in nilfs_copy_dirty_pages() on dirty state mismatch Syzbot reported a kernel BUG triggered within nilfs_copy_dirty_pages(), which copies dirty DAT file folios/pages to its shadow page cache. The BUG occurs when a retrieved dirty folio/page unexpectedly loses its 'dirty' status. This issue arises because, since the commit referenced below, the 'dirty' flag of a folio/page can be cleared asynchronously after the filesystem detects metadata corruption and transitions to read-only mode. Resolve the issue by returning an -EROFS error if the filesystem has transitioned to read-only mode. Also change the behavior to issue a kernel warning only once instead of triggering a kernel BUG when this unexpected 'dirty' state is detected while the filesystem is not in read-only mode.

How do I check if I'm vulnerable to CVE-2026-90418? +

You can use Secably's free Website Scanner to check your website for known vulnerabilities. For infrastructure scanning, use the Port Scanner to identify exposed services that may be affected. Check the vendor advisories linked above for specific patch and version information.