high · 7.1

f2fs: fix fsck inconsistency caused by incorrect nat_entry flag usage

CVE-2026-53368 · published 19 Jul 2026

How serious is it

  • Severity: high, CVSS score 7.1 out of 10.
  • No exploit prediction (EPSS) score yet.
  • Not on the CISA list of exploited vulnerabilities.
  • No public exploit in Exploit-DB.

Is your app affected by CVE-2026-53368?

Paste this prompt into Claude Code, Cursor or any AI coding tool: it runs a free Shippable scan of your project and fixes what it finds. Built with Lovable, Bolt or v0? Scan your live app. Or upload your package file.

Who is affected

  • Linux Linux: 88bd02c9472a166b706284a34a84f1243322d782 to < 270c519bca3a59b6140d176415aff16e4e06f9e3, 88bd02c9472a166b706284a34a84f1243322d782 to < bedb710b63ae1bd617e65d0a8cf6cea1200b3753, 88bd02c9472a166b706284a34a84f1243322d782 to < b28a83ea4934215b5de906c3ee4fbfbc651573e0, 88bd02c9472a166b706284a34a84f1243322d782 to < 019f9dda7f66e55eb94cd32e1d3fff5835f73fbc
  • Linux Linux: 3.18

How to check

  1. Find out whether you run the affected product and which version, then compare it with the versions above.

How to fix

Copies a prompt for Claude Code, Cursor or Codex that asks it to check whether you run this product.
  1. Apply the vendor's update or mitigation from the references below. If there is none yet, limit exposure of the affected service until there is.
  2. If a vulnerable version was live, check your logs and rotate the secrets that server could read.

The advisory

In the Linux kernel, the following vulnerability has been resolved: f2fs: fix fsck inconsistency caused by incorrect nat_entry flag usage f2fs_need_dentry_mark() reads nat_entry flags without mutual exclusion with the checkpoint path, which can result in an incorrect inode block marking state. The scenario is as follows: create & write & fsync 'file A' write checkpoint - f2fs_do_sync_file // inline inode - f2fs_write_inode // inode folio is dirty - f2fs_write_checkpoint - f2fs_flush_merged_writes - f2fs_sync_node_pages - f2fs_fsync_node_pages // no dirty node - f2fs_need_inode_block_update // return true - f2fs_fsync_node_pages // inode dirtied - f2fs_need_dentry_mark //return true - f2fs_flush_nat_entries - f2fs_write_checkpoint end - __write_node_folio // inode with DENT_BIT_SHIFT set SPO, "fsck --dry-run" find inode has already checkpointed but still with DENT_BIT_SHIFT set The state observed by f2fs_need_dentry_mark() can differ from the state observed in __write_node_folio() after acquiring sbi->node_write. The root cause is that the semantics of IS_CHECKPOINTED and HAS_FSYNCED_INODE are only guaranteed after the checkpoint write has fully completed. This patch moves set_dentry_mark() into __write_node_folio() and protects it with the sbi->node_write lock.

Check your whole app

Dependencies are only half of it. Free and read-only: before you push, run npx shippable-dev scan localhost:3000 in your project folder, no account needed. For your live app, you prove it's yours with a one-line tag first.

References

Merged from CVE List. Last updated 25 Oct 2026. All vulnerabilities · RSS · JSON

Get alerts for new exploited vulnerabilities