CVE-2026-8608 | Event Monster <= 2.1.0 - Unauthenticated Insufficient Verification of Data Authenticity to Payment Bypass via em_capture_payment AJAX Action

The Event Monster – Event Management, Events Calendar, Tickets plugin for WordPress is vulnerable to Insufficient Verification of Data Authenticity in versions up to, and including, 2.1.0. This is due to the capture_payment() AJAX handler (registered via wp_ajax_nopriv_em_capture_payment) trusting client-supplied payment data — including transaction ID, amount, and payment status — without performing any server-side verification against the PayPal API or any other payment gateway, and without nonce or capability checks. This makes it possible for unauthenticated attackers to forge payment records, mark bookings as Completed, and obtain confirmation emails containing valid QR code tickets without making any actual payment.

Published: 2026-06-06 Last update: 2026-06-08 Assigner: [email protected] Source: [email protected]

Conclusion & alert: CVE-2026-8608 is rated Low Risk (22.9/100): CVSS Medium severity, with low exploitation likelihood (EPSS 0.15%). Mandatory action: Monitor for updates and reassess as exploit intelligence or EPSS changes.

Risk is dynamic; we continuously reassess and refresh what is shown on this page as upstream context changes.

Exploit prediction scoring system (EPSS) score for CVE-2026-8608

EPSS lead: Daily EPSS estimates relative likelihood of exploitation; percentile ranks this CVE among scored vulnerabilities (higher = more severe relative rank).

# Date Old EPSS score New EPSS score Delta (New - Old)
1 2026-06-15 0.02% 0.15% +0.13%
2 2026-06-06 0.02%

Full EPSS history (2 records total)

Common vulnerability scoring system (CVSS) metrics for CVE-2026-8608

CVSS metrics for this CVE.

Base score Version Severity Vector Exploitability Impact Score source
5.3 3.1 MEDIUM
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:N Click to expand
Attack vector (AV:N)
Could be attacked over the internet or any normal routed network—not just someone sitting at the machine.
Attack complexity (AC:L)
Once they can reach the bug, pulling it off is straightforward—no weird race conditions or rare setup.
Privileges required (PR:N)
No account or special rights needed—anonymous or random user is enough.
User interaction (UI:N)
Nobody has to click “OK” or open a trap file; it can work without a victim helping.
Scope (S:U)
Damage stays in the same “trust bubble” as the broken component—no big spill into unrelated systems.
Confidentiality (C:N)
Doesn’t really leak secrets in a meaningful way.
Integrity (I:L)
Attackers could change some data, but it’s limited—not everything goes.
Availability (A:N)
Service keeps running; no real outage angle.
3.9 1.4 [email protected]

Weakness enumeration for CVE-2026-8608

GitHub Security Advisory for CVE-2026-8608

GHSA-5vph-83m8-9635 · Severity: medium — The Event Monster – Event Management, Events Calendar, Tickets plugin for WordPress is vulnerable...

Affected software / configurations for CVE-2026-8608

Vendor Product Version Raw CPE
No affected products in dataset.

References for CVE-2026-8608

cvelogic Threat Intelligence