{"id":"CVE-2026-121636","title":"Quick Event Manager 9.9.5 - 9.18 - Unauthenticated PayPal IPN Verification Bypass via the 'debug' Parameter","summary":"The Quick Event Manager WordPress plugin before 9.19 does not verify the authenticity of PayPal payment notifications before marking event registrations as paid, which could allow unauthenticated attackers to mark registrations as paid w…","severity":"medium","cvss":5.3,"cvssVector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:N","cvssSource":"cna","cwe":["CWE-345"],"product":"Quick Event Manager","affected":["quick_event_manager >= 9.9.5 < 9.19"],"ssvc":{"exploitation":"none","automatable":"yes","technicalImpact":"partial","timestamp":"2026-11-06T11:41:03.685828Z"},"published":"2026-11-06","updated":"2026-11-06","sourceUpdated":"2026-11-06T11:50:26.062Z","source":"CVEORG","sourceUrl":"https://www.cve.org/CVERecord?id=CVE-2026-121636","references":[{"url":"https://wpscan.com/vulnerability/04b181e1-639c-476f-b66b-2a073bf36829/"}],"tags":["cve.org"],"ingestedAt":"2026-11-06T07:47:15.873Z","epss":0.00114,"epssPercentile":0.01515,"slug":"CVE-2026-121636","body":"## Overview\n\nThe Quick Event Manager WordPress plugin before 9.19 does not verify the authenticity of PayPal payment notifications before marking event registrations as paid, which could allow unauthenticated attackers to mark registrations as paid without making a payment.\n\n## Affected\n\n- `quick_event_manager >= 9.9.5 < 9.19`\n\n## Remediation\n\nRefer to the linked advisories for vendor-supplied fixes and affected version ranges.","depth":"sunlit","depthScore":29,"depthScoreParts":{"impact":29.2,"likelihood":0,"exploitation":0,"ransomware":0},"changes":[]}