Eventin lets unauthenticated callers invalidate paid tickets
Eventin from 4.1.5 up to but not including 4.1.24: When offline/local payment is enabled, an unauthenticated requester can use a publicly exposed nonce to finalize an order without an ownership check. Targeting an existing order resets it and its attendees to pending, invalidating paid tickets. The export does not name the route, order-ID field or callback.
- Component
- Eventin
- Plugin slug
wp-event-solution- Affected
- 4.1.5 to < 4.1.24
- Safe version
4.1.24- Published
- Sep 16, 2026
- Weakness
- CWE-862 — Missing Authorization
This CVE was published Sep 16, 2026 and is one of 45 known issues for this plugin.
Update, patch or deactivate.
Update Eventin to 4.1.24 or later. Require ownership or an appropriate management capability and validate legal payment-state transitions independently of nonce possession. Reconcile unexpected pending orders and affected attendees.
A safe version is available, so updating to that version or later is the preferred remediation. If an immediate update is not practical, consider a targeted application patch or temporarily restricting the affected functionality.
Deactivate only when warranted by your risk profile, or when advised by your hosting provider in the limited circumstances where the vulnerability cannot otherwise be mitigated. If you’re unsure which action is appropriate, contact Fused or your hosting provider for guidance.
Technical description
The Eventin WordPress plugin before 4.1.24 does not properly authorise order finalisation when its offline (local) payment method is enabled, relying on a nonce that is exposed to unauthenticated visitors and never checking that the caller owns the order, allowing unauthenticated attackers to reset any existing order and its attendees to a pending state and thereby invalidate paid tickets.
CVE / CNA vector: CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:L/A:N