CVE-2025-9875: Event Tickets Plugin XSS Vulnerability

CVE-2025-9875 Overview

CVE-2025-9875 is a stored Cross-Site Scripting (XSS) vulnerability in the Event Tickets, RSVPs, Calendar plugin for WordPress. The flaw affects all versions up to and including 1.0.2. It resides in the plugin's ticket_spot shortcode, which fails to properly sanitize user-supplied attributes and escape output. Authenticated users with contributor-level privileges or higher can inject arbitrary JavaScript into pages. The payload executes in the browser of any visitor who accesses the affected page. The issue is tracked under CWE-79: Improper Neutralization of Input During Web Page Generation.

Critical Impact
Authenticated contributors can inject persistent JavaScript that executes against site visitors and administrators, enabling session theft, account takeover, and content manipulation.

Affected Products

WordPress Event Tickets, RSVPs, Calendar plugin (Ticket Spot) versions up to and including 1.0.2
WordPress sites allowing contributor-level or higher accounts
Any page or post rendering the ticket_spot shortcode

Discovery Timeline

2025-10-03 - CVE-2025-9875 published to NVD
2026-10-08 - Last updated in NVD database

Technical Details for CVE-2025-9875

Vulnerability Analysis

The vulnerability exists in the ticket_spot shortcode handler within the plugin's ticket-spot.php file. The handler accepts attributes supplied by the user when the shortcode is placed inside a post or page. These attributes flow directly into the rendered HTML output without sanitization through functions such as sanitize_text_field() or escaping via esc_attr() and esc_html().

Because WordPress contributors can create and edit draft posts, an authenticated attacker with that role or higher can embed the shortcode with malicious attribute values. Once an editor, administrator, or site visitor renders the page, the injected script executes in their browser context. Attackers can leverage this to steal authentication cookies, perform actions on behalf of administrators, redirect visitors, or stage further attacks against the WordPress installation.

The vulnerability is a stored XSS, meaning the payload persists in the database and triggers on every page view until it is removed.

Root Cause

The root cause is insufficient input sanitization and output escaping of shortcode attributes. The plugin treats user-provided attribute values as trusted strings and concatenates them into HTML attributes or inline markup. Review of the vulnerable code location is available at the WordPress Plugin Ticket Spot source.

Attack Vector

The attack requires network access to the WordPress site and valid credentials for an account with contributor privileges or higher. No user interaction beyond visiting an affected page is required to trigger the payload. The scope is changed because script executed in an administrator's session can perform privileged operations outside the plugin itself. See the Wordfence Vulnerability Analysis for additional detail.

No public exploitation code or proof-of-concept has been published. The vulnerability mechanism is described in the referenced advisories without a weaponized exploit.

Detection Methods for CVE-2025-9875

Indicators of Compromise

Posts or pages containing [ticket_spot ...] shortcodes with attribute values that include <script>, onerror=, onload=, javascript:, or encoded script fragments
Unexpected outbound HTTP requests from administrator browsers to attacker-controlled domains after viewing event or ticket pages
New administrator accounts, modified user roles, or altered plugin options created shortly after an administrator visited a page containing the ticket_spot shortcode
Draft or pending posts created by contributor-level accounts that embed shortcodes with suspicious attribute payloads

Detection Strategies

Query the wp_posts table for post_content entries matching the ticket_spot shortcode and inspect attribute values for script tags or event handlers
Review web server logs for POST requests to /wp-admin/post.php and /wp-admin/post-new.php originating from contributor accounts that include shortcode payloads
Enable WordPress audit logging to capture post edits, user role changes, and plugin modifications tied to low-privilege accounts

Monitoring Recommendations

Monitor browser Content Security Policy (CSP) violation reports for inline script execution on pages rendering the plugin's shortcodes
Alert on administrator sessions performing privileged actions immediately after viewing contributor-authored content
Track installations of the Event Tickets, RSVPs, Calendar plugin across the estate and flag versions at or below 1.0.2

How to Mitigate CVE-2025-9875

Immediate Actions Required

Update the Event Tickets, RSVPs, Calendar plugin to the version released in WordPress Changeset #3371344 or later
Audit all existing posts and pages for ticket_spot shortcode usage and remove any attributes containing script content
Review contributor and author accounts for unauthorized or suspicious activity and rotate credentials where abuse is suspected
Invalidate active administrator sessions and force password resets if injected content was executed in administrator browsers

Patch Information

The vendor addressed the issue in a release tracked by WordPress Changeset #3371344. The fix applies proper sanitization and output escaping to attributes passed to the ticket_spot shortcode handler. Site operators should install the patched version through the WordPress plugin update interface or via WP-CLI.

Workarounds

Deactivate the Event Tickets, RSVPs, Calendar plugin until the patched release is deployed
Restrict contributor and author role assignments to trusted users only, and consider removing the ability for lower-privilege accounts to use shortcodes
Deploy a web application firewall (WAF) rule that inspects post content for script payloads inside shortcode attributes
Enforce a strict Content Security Policy that blocks inline script execution on front-end pages

bash

# Update the plugin using WP-CLI
wp plugin update ticket-spot

# Verify the installed version
wp plugin get ticket-spot --field=version

# Search for posts containing the vulnerable shortcode
wp db query "SELECT ID, post_title FROM wp_posts WHERE post_content LIKE '%[ticket_spot%'"