CVE-2026-53320

MEDIUMNVD 5.5Trending — 3 sources updated this week
5.5
EchelonGraph verdictMonitorLow exploitation likelihood right now — keep watching.
  • Lower severity and no public exploit yet
CISA-KEV: Not listedEPSS: 0%CVSS: 5.5Exploit: NoneExposed: 0

No vendor fix yet — apply a workaround or compensating control (WAF / firewall / segmentation) and watch for a patch.

In the Linux kernel, the following vulnerability has been resolved:

nilfs2: reject zero bd_oblocknr in nilfs_ioctl_mark_blocks_dirty()

nilfs_ioctl_mark_blocks_dirty() uses bd_oblocknr to detect dead blocks by comparing it with the current block number bd_blocknr. If they differ, the block is considered dead and skipped.

However, bd_oblocknr should never be 0 since block 0 typically stores the primary superblock and is never a valid GC target block. A corrupted ioctl request with bd_oblocknr set to 0 causes the comparison to incorrectly match when the lookup returns -ENOENT and sets bd_blocknr to 0, bypassing the dead block check and calling nilfs_bmap_mark() on a non-existent block. This causes nilfs_btree_do_lookup() to return -ENOENT, triggering the WARN_ON(ret == -ENOENT).

Fix this by rejecting ioctl requests with bd_oblocknr set to 0 at the beginning of each iteration.

[ryusuke: slightly modified the commit message and comments for accuracy]

CVSS v3
5.5
EG Score
0.0(none)
EPSS
6.9%
KEV
Not listed

Published

June 26, 2026

Last Modified

July 6, 2026

Vendor Advisories for CVE-2026-53320(2)

These vendors published their own advisory mentioning this CVE — often with vendor-specific remediation steps + affected product lists not in NVD.

Data Freshness Timeline

(refreshed 13× in last 7d / 22× in last 30d)

Each row is a source pipeline that fetched or updated this CVE on that date, with what changed. For example, "NVD update" means NVD published or revised its analysis for this CVE; "MITRE cvelistV5" means we ingested or refreshed it from the CNA feed. Most recent first.

  1. 2026-07-06 21:35 UTCNVD updateCVSS v3 → 5.5 · severity → MEDIUM
  2. 2026-07-06 16:27 UTCEPSS rescore
  3. 2026-07-06 16:27 UTCEPSS rescore
  4. 2026-07-06 02:23 UTCEPSS rescore
  5. 2026-07-06 02:23 UTCEPSS rescore
  6. 2026-07-05 16:53 UTCGHSA enrichment
  7. 2026-07-05 02:31 UTCEPSS rescore
  8. 2026-07-05 02:30 UTCEPSS rescore
  9. 2026-07-04 06:31 UTCEPSS rescore
  10. 2026-07-04 06:31 UTCEPSS rescore
  11. 2026-07-02 18:27 UTCGHSA enrichment
  12. 2026-07-01 15:07 UTCEPSS rescore
  13. 2026-06-30 23:22 UTCEPSS rescore
  14. 2026-06-29 20:02 UTCEG score recompute
  15. 2026-06-29 20:02 UTCGHSA enrichment
  16. 2026-06-29 14:06 UTCEPSS rescore
  17. 2026-06-29 14:06 UTCEPSS rescore
  18. 2026-06-28 14:07 UTCEPSS rescore
  19. 2026-06-28 04:56 UTCEPSS rescore
  20. 2026-06-28 04:56 UTCEPSS rescore
  21. 2026-06-26 21:37 UTCEG score recompute
  22. 2026-06-26 21:37 UTCGHSA enrichment

Frequently asked(5)

What is CVE-2026-53320?
CVE-2026-53320 is a medium vulnerability published on June 26, 2026. In the Linux kernel, the following vulnerability has been resolved: nilfs2: reject zero bdoblocknr in nilfsioctlmarkblocks_dirty() nilfsioctlmarkblocksdirty() uses bd_oblocknr to detect dead blocks by comparing it with the current block number bd_blocknr. If they differ, the block is considered…
When was CVE-2026-53320 disclosed?
CVE-2026-53320 was first published in the National Vulnerability Database on June 26, 2026, with the most recent update on July 6, 2026. EchelonGraph re-ingests CVE updates from NVD on a 2-hour cycle, so this page reflects the latest published state.
Is CVE-2026-53320 actively exploited?
CVE-2026-53320 is not currently on CISA's Known Exploited Vulnerabilities catalog. FIRST EPSS estimates a 6.9% percentile likelihood of exploitation in the next 30 days — higher percentiles indicate greater predicted risk.
What is the CVSS score of CVE-2026-53320?
CVE-2026-53320 has a CVSS v3 base score of 5.5 (NVD). EchelonGraph synthesises NVD + CISA KEV + FIRST EPSS + GHSA into a combined EG score of 0.0.
How do I remediate CVE-2026-53320?
Patch to the fixed version published by the affected vendor. Where vendor advisories exist for CVE-2026-53320, EchelonGraph cross-links them in the Vendor Advisories panel below — those typically contain the canonical remediation steps, fixed version numbers, and any vendor-specific mitigations.

Dependency Blast Radius

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