CVE-2026-16618

CRITICALPre-NVD 9.89.8—
EchelonGraph scoreMEDIUM confidence

Score 9.8 from GitHub Security Advisory (severity: CRITICAL) published 2026-08-04. CISA-ADP (Vulnrichment) CVSS v3.1 baseline 9.8; sources differ by 0.0.

Triggered by: GitHub Security Advisory CVSS
Sources: cisa-adp, epss, ghsa
Trending — 3 sources updated this week
9.8EG
EchelonGraph verdictPlan a fixSerious severity, but no confirmed exploitation yet.
  • High severity, but no confirmed exploitation yet
CISA-KEV: Not listedEPSS PROB: 0%CVSS: 9.8Exploit: None knownExposed: 0

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

The Improve SEO WordPress plugin through 2.0.11 does not properly validate uploaded files, checking only the file content type while writing the file with the attacker-supplied extension into a publicly accessible directory, allowing unauthenticated users to upload executable PHP files and achieve remote code execution.

CVSS v3
9.8
EG Score
9.8(medium)
EG Risk
59(Track)
EG Risk 59/100SSVC: Track

EG Risk is EchelonGraph's 0–100 priority score: it fuses intrinsic severity with real-world exploitation and automatability so you can rank equal-severity CVEs and fix the most dangerous first. Higher = act sooner. Distinct from the 0–10 EG Score (severity).

How it’s computed
Severity98% × 45%
Exploitation0% × 40%
Automatability100% × 15%
Action: Routine — remediate on your standard cadence.
EPSS PROB
0%
EPSS %ILE
39%
KEV
Not listed

Published

August 4, 2026

Last Modified

August 26, 2026

Advisory Details (1)

Auto-updated Sep 16, 2026
🔬 Proof of concept available. No patch confirmed yet.
generic🟡 PoC Available

ImproveSEO <= 2.0.13 – Unauthenticated Arbitrary File Upload Leading to Remote Code Execution | CVE 2026-16618 | Plugin Vulnerabilities

https://wpscan.com/vulnerability/3754d4c0-1b67-49a4-a29a-7169446638d1/

Vendor Advisories for CVE-2026-16618(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 32× in last 7d / 160× 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.

Showing the most recent 100 of 299 total refreshes for this CVE.

  1. 2026-09-20 20:54 UTCEG score recompute
  2. 2026-09-20 20:54 UTCGHSA enrichment
  3. 2026-09-20 11:03 UTCGHSA enrichment
  4. 2026-09-20 03:47 UTCGHSA enrichment
  5. 2026-09-19 23:24 UTCGHSA enrichment
  6. 2026-09-19 17:52 UTCEG score recompute
  7. 2026-09-19 17:52 UTCGHSA enrichment
  8. 2026-09-19 13:30 UTCGHSA enrichment
  9. 2026-09-19 04:20 UTCGHSA enrichment
  10. 2026-09-18 23:58 UTCEG score recompute
  11. 2026-09-18 23:58 UTCGHSA enrichment
  12. 2026-09-18 19:27 UTCEPSS rescore
  13. 2026-09-18 19:17 UTCGHSA enrichment
  14. 2026-09-18 14:50 UTCGHSA enrichment
  15. 2026-09-18 09:55 UTCGHSA enrichment
  16. 2026-09-18 05:32 UTCGHSA enrichment
  17. 2026-09-18 01:10 UTCEG score recompute
  18. 2026-09-18 01:10 UTCGHSA enrichment
  19. 2026-09-17 16:16 UTCGHSA enrichment
  20. 2026-09-17 09:57 UTCGHSA enrichment
  21. 2026-09-17 05:35 UTCGHSA enrichment
  22. 2026-09-17 01:12 UTCEG score recompute
  23. 2026-09-17 01:12 UTCGHSA enrichment
  24. 2026-09-16 14:07 UTCEPSS rescore
  25. 2026-09-16 11:17 UTCGHSA enrichment
Show 75 more
  1. 2026-09-16 05:17 UTCEG score recompute
  2. 2026-09-16 05:17 UTCGHSA enrichment
  3. 2026-09-16 05:14 UTCEPSS rescore
  4. 2026-09-15 16:51 UTCGHSA enrichment
  5. 2026-09-15 06:58 UTCEG score recompute
  6. 2026-09-15 06:58 UTCGHSA enrichment
  7. 2026-09-15 01:43 UTCGHSA enrichment
  8. 2026-09-14 14:07 UTCGHSA enrichment
  9. 2026-09-14 09:18 UTCGHSA enrichment
  10. 2026-09-14 04:56 UTCGHSA enrichment
  11. 2026-09-14 00:34 UTCGHSA enrichment
  12. 2026-09-13 20:12 UTCEG score recompute
  13. 2026-09-13 20:12 UTCGHSA enrichment
  14. 2026-09-13 16:46 UTCEPSS rescore
  15. 2026-09-13 15:48 UTCGHSA enrichment
  16. 2026-09-13 11:25 UTCGHSA enrichment
  17. 2026-09-13 07:03 UTCGHSA enrichment
  18. 2026-09-13 02:41 UTCGHSA enrichment
  19. 2026-09-12 22:18 UTCGHSA enrichment
  20. 2026-09-12 17:54 UTCEG score recompute
  21. 2026-09-12 17:54 UTCGHSA enrichment
  22. 2026-09-12 15:00 UTCEPSS rescore
  23. 2026-09-12 13:32 UTCGHSA enrichment
  24. 2026-09-12 09:10 UTCGHSA enrichment
  25. 2026-09-12 04:47 UTCGHSA enrichment
  26. 2026-09-12 00:25 UTCGHSA enrichment
  27. 2026-09-11 19:19 UTCGHSA enrichment
  28. 2026-09-11 14:53 UTCEG score recompute
  29. 2026-09-11 14:53 UTCGHSA enrichment
  30. 2026-09-11 14:52 UTCEPSS rescore
  31. 2026-09-11 09:36 UTCEPSS rescore
  32. 2026-09-11 07:19 UTCGHSA enrichment
  33. 2026-09-11 02:56 UTCGHSA enrichment
  34. 2026-09-10 22:30 UTCGHSA enrichment
  35. 2026-09-10 18:07 UTCGHSA enrichment
  36. 2026-09-10 12:50 UTCEG score recompute
  37. 2026-09-10 12:50 UTCGHSA enrichment
  38. 2026-09-10 09:34 UTCEPSS rescore
  39. 2026-09-10 07:32 UTCGHSA enrichment
  40. 2026-09-10 03:09 UTCGHSA enrichment
  41. 2026-09-09 19:34 UTCGHSA enrichment
  42. 2026-09-09 11:03 UTCGHSA enrichment
  43. 2026-09-09 06:40 UTCEG score recompute
  44. 2026-09-09 06:40 UTCGHSA enrichment
  45. 2026-09-08 22:00 UTCEPSS rescore
  46. 2026-09-08 03:29 UTCGHSA enrichment
  47. 2026-09-07 23:06 UTCGHSA enrichment
  48. 2026-09-07 18:42 UTCEG score recompute
  49. 2026-09-07 18:42 UTCGHSA enrichment
  50. 2026-09-07 16:01 UTCEPSS rescore
  51. 2026-09-06 21:15 UTCGHSA enrichment
  52. 2026-09-06 16:49 UTCEG score recompute
  53. 2026-09-06 16:49 UTCGHSA enrichment
  54. 2026-09-06 13:47 UTCEPSS rescore
  55. 2026-09-06 12:26 UTCGHSA enrichment
  56. 2026-09-06 07:48 UTCGHSA enrichment
  57. 2026-09-06 03:26 UTCGHSA enrichment
  58. 2026-09-05 23:00 UTCGHSA enrichment
  59. 2026-09-05 18:37 UTCEG score recompute
  60. 2026-09-05 18:36 UTCGHSA enrichment
  61. 2026-09-05 08:39 UTCGHSA enrichment
  62. 2026-09-05 04:13 UTCGHSA enrichment
  63. 2026-09-04 14:36 UTCEG score recompute
  64. 2026-09-04 14:36 UTCGHSA enrichment
  65. 2026-09-04 10:13 UTCEG score recompute
  66. 2026-09-04 10:13 UTCGHSA enrichment
  67. 2026-09-04 05:06 UTCEPSS rescore
  68. 2026-09-04 03:26 UTCGHSA enrichment
  69. 2026-09-03 17:33 UTCEG score recompute
  70. 2026-09-03 17:32 UTCGHSA enrichment
  71. 2026-09-03 08:24 UTCEG score recompute
  72. 2026-09-03 08:24 UTCGHSA enrichment
  73. 2026-09-02 14:11 UTCEPSS rescore
  74. 2026-09-02 07:47 UTCGHSA enrichment
  75. 2026-09-01 20:53 UTCEG score recompute

Related CVEs(same CWE)

Frequently asked(5)

What is CVE-2026-16618?
CVE-2026-16618 is a critical vulnerability published on August 4, 2026. The Improve SEO WordPress plugin through 2.0.11 does not properly validate uploaded files, checking only the file content type while writing the file with the attacker-supplied extension into a publicly accessible directory, allowing unauthenticated users to upload executable PHP files and achieve…
When was CVE-2026-16618 disclosed?
CVE-2026-16618 was first published in the National Vulnerability Database on August 4, 2026, with the most recent update on August 26, 2026. EchelonGraph re-ingests CVE updates from NVD on a 2-hour cycle, so this page reflects the latest published state.
Is CVE-2026-16618 actively exploited?
CVE-2026-16618 is not currently on CISA's Known Exploited Vulnerabilities catalog. FIRST EPSS estimates a 0% probability of exploitation in the next 30 days, which ranks it in the top 60.7% of all scored CVEs.
What is the CVSS score of CVE-2026-16618?
CVE-2026-16618 has a CVSS v3.1 base score of 9.8 (CISA-ADP / Vulnrichment enrichment; NVD's own analysis pending).
How do I remediate CVE-2026-16618?
Patch to the fixed version published by the affected vendor. Where vendor advisories exist for CVE-2026-16618, 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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