CVE-2025-4796: Eventin Privilege Escalation Vulnerability

CVE-2025-4796 Overview

CVE-2025-4796 is a privilege escalation vulnerability in the Eventin plugin for WordPress, developed by Themewinter. The flaw affects all versions up to and including 4.0.34. The plugin fails to validate user identity or capability before updating account details in the Eventin\Speaker\Api\SpeakerController::update_item function. Authenticated attackers with contributor-level access can modify any user's email address, including administrators. They can then trigger a password reset to take over the targeted account. The vulnerability is tracked under CWE-639: Authorization Bypass Through User-Controlled Key.

Critical Impact
Contributor-level attackers can take over administrator accounts on WordPress sites running Eventin ≤ 4.0.34, leading to full site compromise.

Affected Products

Themewinter Eventin plugin for WordPress (all versions ≤ 4.0.34)
WordPress sites with the wp-event-solution plugin installed and activated
Sites permitting contributor-level or higher user registration with Eventin enabled

Discovery Timeline

2025-08-08 - CVE-2025-4796 published to the National Vulnerability Database
2025-08-13 - Last updated in NVD database

Technical Details for CVE-2025-4796

Vulnerability Analysis

The vulnerability resides in the update_item method of the SpeakerController class within the Eventin plugin. This REST API endpoint accepts user-supplied parameters to update speaker profile information, including email addresses tied to WordPress user accounts. The endpoint does not verify whether the requesting user has the right to modify the target account.

An attacker with contributor-level access can craft a request to the speaker update endpoint that targets an arbitrary user ID, including a site administrator. By replacing the target's email with one controlled by the attacker, they reroute password reset workflows. The attacker then issues a standard WordPress password reset request and receives the reset link at the attacker-controlled inbox.

Root Cause

The root cause is missing authorization in the Eventin\Speaker\Api\SpeakerController::update_item handler. The function does not call WordPress capability checks such as current_user_can('edit_user', $user_id) before applying changes. It also fails to validate that the target user ID belongs to the requester. This pattern matches [CWE-639], where access control decisions rely on user-controlled identifiers without verification.

Attack Vector

Exploitation requires only network access and a low-privileged WordPress account such as a contributor. No user interaction is required. The attacker authenticates with their own contributor credentials, then sends a crafted REST API request to the vulnerable speaker update endpoint with the administrator's user ID and a new email address. Once the email is changed, the attacker initiates a password reset through wp-login.php?action=lostpassword, completes the reset using the link delivered to their inbox, and logs in as the administrator.

The vulnerability mechanism is detailed in the Wordfence Vulnerability Report and the vulnerable source code.

Detection Methods for CVE-2025-4796

Indicators of Compromise

Unexpected requests to REST API routes under /wp-json/eventin/ referencing speaker update operations from low-privileged accounts.
WordPress audit log entries showing administrator email address changes initiated by non-administrator users.
Password reset events for privileged accounts that immediately follow an email change on the same account.
New administrator logins from unfamiliar IP addresses or geolocations shortly after a reset event.

Detection Strategies

Monitor WordPress REST API access logs for POST or PUT requests to Eventin speaker endpoints originating from contributor or author accounts.
Correlate user_email field changes in the wp_users table with the account that triggered the change to surface mismatches.
Alert when password reset emails for administrator accounts are dispatched within a short window after a profile update.

Monitoring Recommendations

Enable a WordPress activity log plugin to record user metadata changes and REST API calls.
Forward web server and WordPress logs to a centralized SIEM for correlation across authentication, profile change, and reset events.
Review the Eventin plugin version across all WordPress instances and flag any running 4.0.34 or earlier.

How to Mitigate CVE-2025-4796

Immediate Actions Required

Update the Eventin plugin to a version newer than 4.0.34 that includes the fix referenced in WordPress Plugin Changeset 3336972.
Audit all administrator and editor accounts for unauthorized email address changes and reset credentials where tampering is suspected.
Restrict new user registrations and review existing contributor and author accounts for unfamiliar entries.
Rotate WordPress administrator passwords and invalidate active sessions after patching.

Patch Information

Themewinter addressed the vulnerability in the Eventin plugin via changeset 3336972. The fix introduces proper capability checks in the SpeakerController::update_item function to validate the requesting user's authorization before modifying account details. Site administrators should upgrade to the latest available release through the WordPress plugin updater.

Workarounds

Deactivate and remove the Eventin plugin until the patched version is deployed.
Apply a web application firewall rule that blocks unauthenticated and low-privileged access to Eventin speaker REST API routes.
Limit user role assignments so that untrusted users cannot obtain contributor-level access.

bash

# Configuration example: WP-CLI commands to inventory and update the plugin
wp plugin get wp-event-solution --field=version
wp plugin update wp-event-solution
wp user list --role=administrator --fields=ID,user_login,user_email