CVE-2026-15158

CRITICALPre-NVD 9.89.8
EchelonGraph scoreHIGH confidence

Score 9.8 from GitHub Security Advisory (severity: CRITICAL) published 2026-07-09. a secondary CVSS source baseline 9.8; sources differ by 0.0.

Triggered by: GitHub Security Advisory CVSS
Sources: epss, ghsa, secondary
Trending — 4 sources updated this week
9.8
EchelonGraph verdictPlan a fixSerious severity, but no confirmed exploitation yet.
  • High severity, but no confirmed exploitation yet
CISA-KEV: Not listedEPSS: 1%CVSS: 9.8Exploit: NoneExposed: 0

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

The Blocksy Companion plugin for WordPress is vulnerable to Arbitrary File Upload in all versions up to, and including, 2.1.46 via the save_attachments function. This is due to the Custom Fonts extension registering a wp_check_filetype_and_ext filter that approves any filename containing .woff2 or .ttf as a substring via strpos() rather than validating that those strings appear as the final extension via PATHINFO_EXTENSION — allowing double-extension filenames such as shell.woff2.php to pass MIME validation and be handled as permitted font files. This makes it possible for unauthenticated attackers to upload files that may be executable, which makes remote code execution possible. This vulnerability is only exploitable when the premium version of the plugin (blocksy-companion-pro) is installed with both the WooCommerce Extra (Advanced Reviews) and Custom Fonts extensions active; the free blocksy-companion plugin does not contain the vulnerable code paths.

CVSS v3
9.8
EG Score
9.8(high)
EPSS
58.6%
KEV
Not listed

Published

July 9, 2026

Last Modified

July 9, 2026

Vendor Advisories for CVE-2026-15158(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 80× in last 7d / 80× 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. 2026-07-15 05:39 UTCEG score recompute
  2. 2026-07-15 05:39 UTCGHSA enrichment
  3. 2026-07-15 02:00 UTCEPSS rescore
  4. 2026-07-15 01:45 UTCEG score recompute
  5. 2026-07-15 01:45 UTCGHSA enrichment
  6. 2026-07-14 21:52 UTCEG score recompute
  7. 2026-07-14 21:52 UTCGHSA enrichment
  8. 2026-07-14 17:59 UTCEG score recompute
  9. 2026-07-14 17:59 UTCGHSA enrichment
  10. 2026-07-14 13:53 UTCEG score recompute
  11. 2026-07-14 13:53 UTCGHSA enrichment
  12. 2026-07-14 10:01 UTCEG score recompute
  13. 2026-07-14 10:00 UTCGHSA enrichment
  14. 2026-07-14 06:07 UTCEG score recompute
  15. 2026-07-14 06:07 UTCGHSA enrichment
  16. 2026-07-14 02:12 UTCEG score recompute
  17. 2026-07-14 02:12 UTCGHSA enrichment
  18. 2026-07-13 22:30 UTCEPSS rescore
  19. 2026-07-13 22:19 UTCEG score recompute
  20. 2026-07-13 22:19 UTCGHSA enrichment
  21. 2026-07-13 18:26 UTCEG score recompute
  22. 2026-07-13 18:26 UTCGHSA enrichment
  23. 2026-07-13 14:33 UTCEG score recompute
  24. 2026-07-13 14:33 UTCGHSA enrichment
  25. 2026-07-13 10:39 UTCEG score recompute
Show 55 more
  1. 2026-07-13 10:39 UTCGHSA enrichment
  2. 2026-07-13 06:40 UTCEG score recompute
  3. 2026-07-13 06:40 UTCGHSA enrichment
  4. 2026-07-13 06:12 UTCEPSS rescore
  5. 2026-07-13 02:47 UTCEG score recompute
  6. 2026-07-13 02:47 UTCGHSA enrichment
  7. 2026-07-12 22:54 UTCEG score recompute
  8. 2026-07-12 22:54 UTCGHSA enrichment
  9. 2026-07-12 19:01 UTCEG score recompute
  10. 2026-07-12 19:01 UTCGHSA enrichment
  11. 2026-07-12 15:08 UTCEG score recompute
  12. 2026-07-12 15:08 UTCGHSA enrichment
  13. 2026-07-12 11:15 UTCEG score recompute
  14. 2026-07-12 11:15 UTCGHSA enrichment
  15. 2026-07-12 07:21 UTCEG score recompute
  16. 2026-07-12 07:21 UTCGHSA enrichment
  17. 2026-07-12 05:46 UTCEPSS rescore
  18. 2026-07-12 03:28 UTCEG score recompute
  19. 2026-07-12 03:28 UTCGHSA enrichment
  20. 2026-07-11 23:35 UTCEG score recompute
  21. 2026-07-11 23:35 UTCGHSA enrichment
  22. 2026-07-11 19:42 UTCEG score recompute
  23. 2026-07-11 19:42 UTCGHSA enrichment
  24. 2026-07-11 15:49 UTCEG score recompute
  25. 2026-07-11 15:49 UTCGHSA enrichment
  26. 2026-07-11 11:56 UTCEG score recompute
  27. 2026-07-11 11:56 UTCGHSA enrichment
  28. 2026-07-11 08:27 UTCEPSS rescore
  29. 2026-07-11 08:04 UTCEG score recompute
  30. 2026-07-11 08:04 UTCGHSA enrichment
  31. 2026-07-11 04:10 UTCEG score recompute
  32. 2026-07-11 04:10 UTCGHSA enrichment
  33. 2026-07-11 00:13 UTCEG score recompute
  34. 2026-07-11 00:13 UTCGHSA enrichment
  35. 2026-07-10 20:19 UTCEG score recompute
  36. 2026-07-10 20:19 UTCGHSA enrichment
  37. 2026-07-10 16:26 UTCEG score recompute
  38. 2026-07-10 16:26 UTCGHSA enrichment
  39. 2026-07-10 12:33 UTCEG score recompute
  40. 2026-07-10 12:32 UTCGHSA enrichment
  41. 2026-07-10 08:38 UTCEG score recompute
  42. 2026-07-10 08:38 UTCGHSA enrichment
  43. 2026-07-10 04:45 UTCEG score recompute
  44. 2026-07-10 04:45 UTCGHSA enrichment
  45. 2026-07-10 00:53 UTCEG score recompute
  46. 2026-07-10 00:53 UTCGHSA enrichment
  47. 2026-07-09 20:59 UTCEG score recompute
  48. 2026-07-09 20:59 UTCGHSA enrichment
  49. 2026-07-09 19:10 UTCEPSS rescore
  50. 2026-07-09 17:06 UTCEG score recompute
  51. 2026-07-09 17:06 UTCGHSA enrichment
  52. 2026-07-09 13:13 UTCEG score recompute
  53. 2026-07-09 13:13 UTCGHSA enrichment
  54. 2026-07-09 09:20 UTCEG score recompute
  55. 2026-07-09 09:20 UTCMITRE cvelistV5first tracked

Frequently asked(5)

What is CVE-2026-15158?
CVE-2026-15158 is a critical vulnerability published on July 9, 2026. The Blocksy Companion plugin for WordPress is vulnerable to Arbitrary File Upload in all versions up to, and including, 2.1.46 via the saveattachments function. This is due to the Custom Fonts extension registering a wpcheckfiletypeandext filter that approves any filename containing .woff2 or .ttf…
When was CVE-2026-15158 disclosed?
CVE-2026-15158 was first published in the National Vulnerability Database on July 9, 2026. EchelonGraph re-ingests CVE updates from NVD on a 2-hour cycle, so this page reflects the latest published state.
Is CVE-2026-15158 actively exploited?
CVE-2026-15158 is not currently on CISA's Known Exploited Vulnerabilities catalog. FIRST EPSS estimates a 58.6% percentile likelihood of exploitation in the next 30 days — higher percentiles indicate greater predicted risk.
What is the CVSS score of CVE-2026-15158?
CVE-2026-15158 has a CVSS v3 base score of 9.8 (NVD).
How do I remediate CVE-2026-15158?
Patch to the fixed version published by the affected vendor. Where vendor advisories exist for CVE-2026-15158, 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

Explore the affected products and dependency analysis for CVE-2026-15158

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