---
id: "CVE-2026-121636"
page: "https://infrastack.ai/live/CVE-2026-121636"
kind: "vulnerability"
aliases: ["CVE-2026-121636"]
title: "Quick Event Manager WordPress plugin lets attackers fake PayPal paid registrations"
severity: "medium"
cvss: 5.3
epss: null
exploited: false
status: "open"
category: "package"
products: []
ecosystems: []
tags: ["event-registration", "package", "paypal", "wordpress", "wordpress-plugin"]
not_affected_if: ["paypal-not-used", "plugin-9.19-or-later", "plugin-not-installed"]
published_at: "2026-11-06T08:17:20+00:00"
first_seen_at: "2026-11-06T08:40:33+00:00"
updated_at: "2026-11-06T08:42:39+00:00"
sources: [{"source": "nvd", "url": "https://nvd.nist.gov/vuln/detail/CVE-2026-121636", "first_seen_at": "2026-11-06T08:40:33+00:00"}]
exploit_sources: []
---

# Quick Event Manager WordPress plugin lets attackers fake PayPal paid registrations

Link for people: https://infrastack.ai/live/CVE-2026-121636 (this .md is for agents)

The Quick Event Manager WordPress plugin before 9.19 does not check that PayPal payment notifications are genuine before marking event registrations as paid. An unauthenticated attacker can mark registrations as paid without paying.

_Summary, check and fix written by a model from the sources; labelled as such._

## How to check

- Check the installed version of the Quick Event Manager plugin in the WordPress admin plugin list, or in the plugin's main file header.
- Confirm whether the site uses PayPal payments for event registrations.

## Fix

- Quick Event Manager plugin: move to a version at or above `9.19`.

## Timeline

- 2026-11-06T08:40:33+00:00 nvd https://nvd.nist.gov/vuln/detail/CVE-2026-121636

## From the sources

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 without making a payment.

---

_Free to read, with fair use of about 60 pages a minute. For higher limits or API access: sales@infrastack.ai_