CVE-2026-53368
f2fs: fix fsck inconsistency caused by incorrect nat_entry flag usage
Description
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.
INFO
Published Date :
July 19, 2026, 9:17 a.m.
Last Modified :
July 29, 2026, 4:55 p.m.
Remotely Exploit :
No
Source :
416baaa9-dc9f-4396-8d5f-8c081fb06d67
CVSS Scores
| Score | Version | Severity | Vector | Exploitability Score | Impact Score | Source |
|---|---|---|---|---|---|---|
| CVSS 3.1 | HIGH | 416baaa9-dc9f-4396-8d5f-8c081fb06d67 |
Solution
- Apply the provided patch to the Linux kernel.
- Ensure sbi->node_write lock protects dentry mark updates.
- Update the Linux kernel to a patched version.
References to Advisories, Solutions, and Tools
Here, you will find a curated list of external links that provide in-depth
information, practical solutions, and valuable tools related to
CVE-2026-53368.
CWE - Common Weakness Enumeration
While CVE identifies
specific instances of vulnerabilities, CWE categorizes the common flaws or
weaknesses that can lead to vulnerabilities. CVE-2026-53368 is
associated with the following CWEs:
Common Attack Pattern Enumeration and Classification (CAPEC)
Common Attack Pattern Enumeration and Classification
(CAPEC)
stores attack patterns, which are descriptions of the common attributes and
approaches employed by adversaries to exploit the CVE-2026-53368
weaknesses.
We scan GitHub repositories to detect new proof-of-concept exploits. Following list is a collection of public exploits and proof-of-concepts, which have been published on GitHub (sorted by the most recently updated).
Results are limited to the first 15 repositories due to potential performance issues.
The following list is the news that have been mention
CVE-2026-53368 vulnerability anywhere in the article.
The following table lists the changes that have been made to the
CVE-2026-53368 vulnerability over time.
Vulnerability history details can be useful for understanding the evolution of a vulnerability, and for identifying the most recent changes that may impact the vulnerability's severity, exploitability, or other characteristics.
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Initial Analysis by [email protected]
Jul. 29, 2026
Action Type Old Value New Value Added CWE NVD-CWE-noinfo Added CPE Configuration OR *cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:* versions from (including) 6.19 up to (excluding) 7.0.7 *cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:* versions from (including) 3.18 up to (excluding) 6.18.30 Added Reference Type kernel.org: https://git.kernel.org/stable/c/019f9dda7f66e55eb94cd32e1d3fff5835f73fbc Types: Patch Added Reference Type kernel.org: https://git.kernel.org/stable/c/b28a83ea4934215b5de906c3ee4fbfbc651573e0 Types: Patch Added Reference Type kernel.org: https://git.kernel.org/stable/c/bedb710b63ae1bd617e65d0a8cf6cea1200b3753 Types: Patch -
CVE Modified by 416baaa9-dc9f-4396-8d5f-8c081fb06d67
Jul. 20, 2026
Action Type Old Value New Value Added CVSS V3.1 AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:H/A:H -
New CVE Received by 416baaa9-dc9f-4396-8d5f-8c081fb06d67
Jul. 19, 2026
Action Type Old Value New Value Added Affected [{'repo': 'https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git', 'vendor': 'Linux', 'product': 'Linux', 'versions': [{'status': 'affected', 'version': '88bd02c9472a166b706284a34a84f1243322d782', 'lessThan': 'bedb710b63ae1bd617e65d0a8cf6cea1200b3753', 'versionType': 'git'}, {'status': 'affected', 'version': '88bd02c9472a166b706284a34a84f1243322d782', 'lessThan': 'b28a83ea4934215b5de906c3ee4fbfbc651573e0', 'versionType': 'git'}, {'status': 'affected', 'version': '88bd02c9472a166b706284a34a84f1243322d782', 'lessThan': '019f9dda7f66e55eb94cd32e1d3fff5835f73fbc', 'versionType': 'git'}], 'programFiles': ['fs/f2fs/node.c'], 'defaultStatus': 'unaffected'}, {'repo': 'https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git', 'vendor': 'Linux', 'product': 'Linux', 'versions': [{'status': 'affected', 'version': '3.18'}, {'status': 'unaffected', 'version': '0', 'lessThan': '3.18', 'versionType': 'semver'}, {'status': 'unaffected', 'version': '6.18.30', 'versionType': 'semver', 'lessThanOrEqual': '6.18.*'}, {'status': 'unaffected', 'version': '7.0.7', 'versionType': 'semver', 'lessThanOrEqual': '7.0.*'}, {'status': 'unaffected', 'version': '7.1', 'versionType': 'original_commit_for_fix', 'lessThanOrEqual': '*'}], 'programFiles': ['fs/f2fs/node.c'], 'defaultStatus': 'affected'}] Added Description 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. Added Reference https://git.kernel.org/stable/c/019f9dda7f66e55eb94cd32e1d3fff5835f73fbc Added Reference https://git.kernel.org/stable/c/b28a83ea4934215b5de906c3ee4fbfbc651573e0 Added Reference https://git.kernel.org/stable/c/bedb710b63ae1bd617e65d0a8cf6cea1200b3753