CVE-2024-10263: Tickera WordPress Plugin RCE Vulnerability

CVE-2024-10263 Overview

CVE-2024-10263 is an arbitrary shortcode execution vulnerability affecting the Tickera – WordPress Event Ticketing plugin. All versions up to and including 3.5.4.4 are affected. The plugin fails to properly validate a value before passing it to the WordPress do_shortcode function. Unauthenticated attackers can reach this code path over the network and execute arbitrary shortcodes registered on the target site. The issue is tracked under CWE-94: Improper Control of Generation of Code.

Critical Impact

Unauthenticated attackers can invoke arbitrary WordPress shortcodes, enabling content disclosure, abuse of privileged shortcodes from other plugins, and potential pivoting to higher-impact attacks depending on the shortcodes registered on the site.

Affected Products

• Tickera – WordPress Event Ticketing plugin versions <= 3.5.4.4
• WordPress sites running Tickera with default configurations
• All site installations exposed to the public internet running vulnerable plugin versions

Discovery Timeline

• 2024-11-05 - CVE-2024-10263 published to the National Vulnerability Database
• 2024-11-08 - Last updated in the NVD database

Technical Details for CVE-2024-10263

Vulnerability Analysis

The Tickera plugin exposes an action handler that accepts attacker-controlled input and forwards it to WordPress's do_shortcode function without proper validation. do_shortcode parses a string and executes any registered shortcode tags it contains. Because the action is reachable without authentication, any visitor can craft a request that triggers shortcode evaluation server-side.

Shortcode execution is not inherently dangerous, but registered shortcodes often perform privileged operations. Examples include rendering private content, listing user data, dispatching emails, or returning data scoped to administrative users. An attacker who can call arbitrary shortcodes effectively borrows the privileges of whichever shortcode handlers are installed.

The impact scales with the other plugins present on the site. A site with shortcodes that expose order data, user metadata, or file contents allows information disclosure. Sites with shortcodes that trigger server actions allow integrity-affecting operations.

Root Cause

The root cause is missing input validation on a value consumed by do_shortcode inside a publicly accessible action. The plugin treats the input as trusted and renders it through the shortcode engine. This is a textbook [CWE-94] code generation flaw, where user input controls the code path executed by the interpreter.

Attack Vector

The attack vector is network-based and requires no authentication or user interaction. An attacker sends an HTTP request to the vulnerable Tickera action endpoint with a payload containing one or more shortcode tags. The plugin invokes do_shortcode on the attacker payload, and the WordPress shortcode engine resolves and executes each registered tag found in the string. The response, side effects, or both can then be leveraged by the attacker.

The vulnerability mechanism is described in the Wordfence Vulnerability Report and the upstream fix is visible in the WordPress plugin changeset 3179272.

Detection Methods for CVE-2024-10263

Indicators of Compromise

• HTTP POST or GET requests to Tickera plugin action endpoints containing bracketed shortcode syntax such as [shortcode_name] in parameter values
• Unauthenticated requests to admin-ajax.php or admin-post.php invoking Tickera actions from external IP addresses
• Anomalous outbound responses from the site that include rendered content normally restricted to authenticated users
• Web server logs showing repeated probing of Tickera endpoints with varying shortcode payloads

Detection Strategies

• Inspect WordPress access logs for request bodies and query strings containing %5B (URL-encoded [) targeting Tickera action handlers
• Enable WordPress debug logging and monitor calls to do_shortcode originating from Tickera action callbacks
• Deploy a web application firewall rule that flags shortcode tags submitted by unauthenticated sessions to plugin endpoints
• Correlate plugin version inventory with the affected range <= 3.5.4.4 to identify exposed installations

Monitoring Recommendations

• Track HTTP response sizes and content patterns from Tickera endpoints for anomalies suggesting data leakage
• Alert on bursts of requests targeting the same Tickera action from a single source IP
• Audit which shortcodes are registered on the site and flag any that expose sensitive data or perform privileged operations
• Monitor WordPress audit logs for shortcode-driven side effects such as outgoing emails or unexpected content rendering

How to Mitigate CVE-2024-10263

Immediate Actions Required

• Update the Tickera plugin to a version newer than 3.5.4.4 that contains the fix from changeset 3179272
• Inventory all WordPress sites in the environment and identify any running vulnerable Tickera versions
• Review web server and WordPress logs for prior exploitation attempts against Tickera endpoints
• Audit shortcodes registered by other installed plugins to understand exposure if exploitation occurred

Patch Information

The vendor addressed CVE-2024-10263 in the Tickera plugin update tracked by WordPress Trac changeset 3179272. The patch adds validation on the input passed to do_shortcode, preventing attacker-controlled shortcode tags from being processed by the vulnerable action handler. Administrators should apply the update through the WordPress plugin dashboard or via WP-CLI. Additional context is available in the Wordfence Vulnerability Report.

Workarounds

• Disable the Tickera plugin until the patched version can be deployed if immediate updating is not possible
• Restrict access to Tickera action endpoints at the web application firewall by blocking unauthenticated requests containing [ characters in parameters
• Remove or disable other plugins that register sensitive shortcodes to reduce blast radius until patching is complete
• Place the WordPress administrative interface and AJAX endpoints behind IP allowlists where business requirements permit

# Update Tickera via WP-CLI to remediate CVE-2024-10263
wp plugin update tickera-event-ticketing-system

# Verify installed version is above 3.5.4.4
wp plugin get tickera-event-ticketing-system --field=version

# Temporary workaround: deactivate the plugin until patched
wp plugin deactivate tickera-event-ticketing-system