CVE-2026-16618

CRITICALPre-NVD 9.89.8—
EchelonGraph scoreHIGH 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(high)
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
38%
KEV
Not listed

Published

August 4, 2026

Last Modified

August 4, 2026

Advisory Details (1)

Auto-updated Aug 18, 2026
🔬 Proof of concept available. No patch confirmed yet.
generic🟡 PoC Available

ImproveSEO <= 2.0.11 – 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 52× in last 7d / 130× 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 130 total refreshes for this CVE.

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

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. 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 61.6% 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.

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