CVE-2026-11964

CRITICALPre-NVD 9.19.1—
EchelonGraph scoreMEDIUM confidence

Score 9.1 from GitHub Security Advisory (severity: CRITICAL) published 2026-07-13. CISA-ADP (Vulnrichment) CVSS v3.1 baseline 9.1; sources differ by 0.0.

Triggered by: GitHub Security Advisory CVSS
Sources: cisa-adp, epss, ghsa
Trending — 3 sources updated this weekElevated
9.1EG
EchelonGraph verdictPlan a fixSerious severity, but no confirmed exploitation yet.
  • High severity, but no confirmed exploitation yet
CISA-KEV: Not listedEPSS PROB: 0%CVSS: 9.1Exploit: Elevated riskExposed: 0

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

The User Registration & Membership WordPress plugin before 5.2.2 does not verify the authenticity of incoming payment-provider webhook notifications before acting on them, allowing unauthenticated attackers to forge a payment-approved event and activate a paid membership subscription without completing a real payment.

CVSS v3
9.1
EG Score
9.1(medium)
EG Risk
72(Attend)
EG Risk 72/100SSVC: Attend

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
Severity91% × 45%
Exploitation40% × 40%
Automatability100% × 15%
Action: Remediate soon — notable exploitation risk.
EPSS PROB
0%
EPSS %ILE
38%
KEV
Not listed

Published

July 13, 2026

Last Modified

July 13, 2026

Advisory Details (1)

Auto-updated Aug 30, 2026
🔬 Proof of concept available. No patch confirmed yet.
generic🟡 PoC Available

User Registration & Membership < 5.2.2 – Unauthenticated PayPal Webhook Signature Verification Bypass Leading to Membership Activation | CVE 2026-11964 | Plugin Vulnerabilities

https://wpscan.com/vulnerability/faf55649-8f76-4abf-a6b9-0d0774e22d29/

Vendor Advisories for CVE-2026-11964(1)

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 32× in last 7d / 215× 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 283 total refreshes for this CVE.

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

Frequently asked(5)

What is CVE-2026-11964?
CVE-2026-11964 is a critical vulnerability published on July 13, 2026. The User Registration & Membership WordPress plugin before 5.2.2 does not verify the authenticity of incoming payment-provider webhook notifications before acting on them, allowing unauthenticated attackers to forge a payment-approved event and activate a paid membership subscription without…
When was CVE-2026-11964 disclosed?
CVE-2026-11964 was first published in the National Vulnerability Database on July 13, 2026. EchelonGraph re-ingests CVE updates from NVD on a 2-hour cycle, so this page reflects the latest published state.
Is CVE-2026-11964 actively exploited?
CVE-2026-11964 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 62.4% of all scored CVEs.
What is the CVSS score of CVE-2026-11964?
CVE-2026-11964 has a CVSS v3.1 base score of 9.1 (CISA-ADP / Vulnrichment enrichment; NVD's own analysis pending).
How do I remediate CVE-2026-11964?
Patch to the fixed version published by the affected vendor. Where vendor advisories exist for CVE-2026-11964, 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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