CVE-2026-5821

HIGHPre-NVD 8.18.1—
EchelonGraph scoreHIGH confidence

Score 8.1 from GitHub Security Advisory (severity: HIGH) published 2026-07-02. a secondary CVSS source baseline 8.1; sources differ by 0.0.

Triggered by: GitHub Security Advisory CVSS
Sources: epss, ghsa, secondary
Trending — 3 sources updated this week
8.1
EchelonGraph verdictPlan a fixSerious severity, but no confirmed exploitation yet.
  • High severity, but no confirmed exploitation yet
CISA-KEV: Not listedEPSS: 0%CVSS: 8.1Exploit: NoneExposed: 0

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

The Image Optimizer plugin for WordPress is vulnerable to arbitrary file deletion in versions up to and including 1.7.4. This is due to insufficient path validation in the Image_Backup::remove() function where backup file paths stored in post meta are used directly in file deletion operations without verifying they are within the uploads directory. The plugin stores backup file paths in the image_optimizer_metadata post meta field and trusts these paths completely when deleting backups on the delete_attachment hook. An authenticated attacker with Author-level access can edit the image_optimizer_metadata post meta on their own attachments via WordPress's Custom Fields interface, injecting arbitrary absolute file paths into the backups array. When the attacker subsequently deletes the attachment, the plugin calls File_System::delete() on each path without validation. This makes it possible for authenticated attackers, with Author-level access and above, to delete arbitrary files on the server within the web server's filesystem permissions, potentially leading to denial of service, data loss, or security degradation.

CVSS v3
8.1
EG Score
8.1(high)
EPSS
27.4%
KEV
Not listed

Published

July 2, 2026

Last Modified

July 2, 2026

References (8)

Vendor Advisories for CVE-2026-5821(1)

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

Weakness Classification(1)

MITRE Common Weakness Enumeration — the root-cause categories this CVE belongs to.

Data Freshness Timeline

(refreshed 30× in last 7d / 30× 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 22:59 UTCEG score recompute
  2. 2026-07-06 22:59 UTCGHSA enrichment
  3. 2026-07-06 16:27 UTCEPSS rescore
  4. 2026-07-06 16:27 UTCEPSS rescore
  5. 2026-07-06 11:49 UTCEG score recompute
  6. 2026-07-06 11:49 UTCGHSA enrichment
  7. 2026-07-06 02:23 UTCEPSS rescore
  8. 2026-07-06 02:23 UTCEPSS rescore
  9. 2026-07-06 00:38 UTCEG score recompute
  10. 2026-07-06 00:38 UTCGHSA enrichment
  11. 2026-07-05 13:28 UTCEG score recompute
  12. 2026-07-05 13:28 UTCGHSA enrichment
  13. 2026-07-05 02:31 UTCEPSS rescore
  14. 2026-07-05 02:30 UTCEPSS rescore
  15. 2026-07-05 02:18 UTCEG score recompute
  16. 2026-07-05 02:18 UTCGHSA enrichment
  17. 2026-07-04 15:09 UTCEG score recompute
  18. 2026-07-04 15:09 UTCGHSA enrichment
  19. 2026-07-04 06:31 UTCEPSS rescore
  20. 2026-07-04 06:31 UTCEPSS rescore
  21. 2026-07-04 03:58 UTCEG score recompute
  22. 2026-07-04 03:58 UTCGHSA enrichment
  23. 2026-07-03 16:48 UTCEG score recompute
  24. 2026-07-03 16:48 UTCGHSA enrichment
  25. 2026-07-03 05:37 UTCEG score recompute
Show 5 more
  1. 2026-07-03 05:37 UTCGHSA enrichment
  2. 2026-07-02 18:27 UTCEG score recompute
  3. 2026-07-02 18:27 UTCGHSA enrichment
  4. 2026-07-02 07:18 UTCEG score recompute
  5. 2026-07-02 07:18 UTCGHSA enrichment

Frequently asked(5)

What is CVE-2026-5821?
CVE-2026-5821 is a high vulnerability published on July 2, 2026. The Image Optimizer plugin for WordPress is vulnerable to arbitrary file deletion in versions up to and including 1.7.4. This is due to insufficient path validation in the ImageBackup::remove() function where backup file paths stored in post meta are used directly in file deletion operations…
When was CVE-2026-5821 disclosed?
CVE-2026-5821 was first published in the National Vulnerability Database on July 2, 2026. EchelonGraph re-ingests CVE updates from NVD on a 2-hour cycle, so this page reflects the latest published state.
Is CVE-2026-5821 actively exploited?
CVE-2026-5821 is not currently on CISA's Known Exploited Vulnerabilities catalog. FIRST EPSS estimates a 27.4% percentile likelihood of exploitation in the next 30 days — higher percentiles indicate greater predicted risk.
What is the CVSS score of CVE-2026-5821?
CVE-2026-5821 has a CVSS v3 base score of 8.1 (NVD).
How do I remediate CVE-2026-5821?
Patch to the fixed version published by the affected vendor. Where vendor advisories exist for CVE-2026-5821, 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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