CVE-2024-56251 Overview
CVE-2024-56251 is a Cross-Site Request Forgery (CSRF) vulnerability in the Event Espresso 4 Decaf WordPress plugin (event-espresso-decaf). The issue affects all versions up to and including 5.0.28.decaf. An attacker can trick an authenticated user into submitting an unintended state-changing request to the plugin. Successful exploitation requires user interaction, such as clicking a crafted link or visiting an attacker-controlled page while authenticated. The vulnerability is categorized under [CWE-352] Cross-Site Request Forgery.
Critical Impact
An attacker can perform unauthorized actions on behalf of an authenticated Event Espresso administrator, resulting in limited integrity impact to plugin data and configuration.
Affected Products
- Event Espresso 4 Decaf plugin for WordPress
- All versions from initial release through 5.0.28.decaf
- WordPress sites running the event-espresso-decaf plugin
Discovery Timeline
- 2025-01-02 - CVE-2024-56251 published to NVD
- 2026-06-17 - Last updated in NVD database
Technical Details for CVE-2024-56251
Vulnerability Analysis
The Event Espresso 4 Decaf plugin fails to enforce anti-CSRF protections on one or more state-changing request handlers. WordPress provides a built-in nonce mechanism through functions such as wp_nonce_field() and check_admin_referer(), but the affected endpoints do not validate a valid nonce before processing the request. An attacker who lures an authenticated administrator to a malicious page can trigger form submissions or requests that the plugin treats as legitimate. The attack is network-based, requires no privileges on the target site, and requires user interaction from the victim. The EPSS score sits at 0.178%, reflecting low observed exploitation activity.
Root Cause
The root cause is missing or improperly verified CSRF tokens on privileged plugin endpoints. Without server-side validation of a wp_nonce or equivalent unpredictable token, the plugin cannot distinguish a legitimate administrator action from a forged cross-origin request initiated by the victim's browser.
Attack Vector
Exploitation proceeds by hosting a page containing a hidden form or auto-submitting JavaScript that targets a vulnerable Event Espresso admin endpoint. When an authenticated WordPress administrator visits the page, the browser attaches the session cookie and submits the forged request. The plugin processes the request and performs the state change requested by the attacker. See the Patchstack CSRF Vulnerability Report for technical details on the affected code paths.
Detection Methods for CVE-2024-56251
Indicators of Compromise
- Unexpected changes to Event Espresso plugin configuration, events, or registration data made by administrator accounts.
- HTTP POST requests to event-espresso-decaf admin endpoints with a Referer header pointing to an external domain.
- Administrator sessions submitting privileged requests immediately after visiting an unrelated external site.
Detection Strategies
- Review web server access logs for requests to wp-admin/admin.php or admin-ajax.php with Event Espresso action parameters and non-local Referer values.
- Enable WordPress audit logging to correlate administrator actions with user browsing activity.
- Inspect the plugin version in use and flag any deployment running 5.0.28.decaf or earlier.
Monitoring Recommendations
- Monitor for anomalous administrator activity outside of normal maintenance windows.
- Alert on Event Espresso configuration modifications that lack a corresponding valid session context.
- Track outbound browsing patterns for administrators using dedicated management workstations.
How to Mitigate CVE-2024-56251
Immediate Actions Required
- Update the Event Espresso 4 Decaf plugin to a version later than 5.0.28.decaf as soon as a fixed release is available from the vendor.
- Audit administrator accounts and remove unused or over-privileged users to reduce exposure.
- Require administrators to use dedicated browsers or browser profiles for WordPress management.
Patch Information
At the time of publication, the vulnerability affects all versions through 5.0.28.decaf. Consult the Patchstack CSRF Vulnerability Report for the current patch status and vendor-supplied fix.
Workarounds
- Deactivate the event-espresso-decaf plugin until a patched version is installed if event management is not business-critical.
- Deploy a Web Application Firewall rule that requires a valid Referer and Origin header for Event Espresso admin requests.
- Enforce short administrator session lifetimes and require re-authentication for privileged plugin actions.
# Example WordPress WP-CLI commands to check plugin status and disable if needed
wp plugin get event-espresso-decaf --field=version
wp plugin deactivate event-espresso-decaf
Disclaimer: This content was generated using AI. While we strive for accuracy, please verify critical information with official sources.
