Can you explain this vulnerability to me?

The Envira Gallery for WordPress plugin is vulnerable to Stored Cross-Site Scripting (XSS) via the 'justified_gallery_theme' parameter in all versions up to and including 1.12.3. This vulnerability arises due to insufficient input sanitization and output escaping.

An authenticated attacker with Author-level access or higher can exploit this vulnerability by injecting arbitrary web scripts into pages. These scripts will execute whenever any user accesses the injected page, potentially compromising user data or site integrity.

Useful 0 Not Useful 0

How can this vulnerability impact me? :

This vulnerability allows attackers with Author-level access to inject malicious scripts that execute in the browsers of users who visit the affected pages.

• It can lead to theft of user credentials or session cookies.
• It may enable attackers to perform actions on behalf of users without their consent.
• It can result in defacement or unauthorized content injection on the website.
• The vulnerability has a CVSS v3.1 base score of 6.4, indicating a medium severity impact with low attack complexity but requiring privileges.

Useful 0 Not Useful 0

How does this vulnerability affect compliance with common standards and regulations (like GDPR, HIPAA)?:

I don't know

Useful 0 Not Useful 0

How can this vulnerability be detected on my network or system? Can you suggest some commands?

The vulnerability involves Stored Cross-Site Scripting (XSS) via the 'justified_gallery_theme' parameter in the Envira Gallery for WordPress plugin versions up to 1.12.3. Detection would involve identifying if this plugin and vulnerable versions are installed and if the 'justified_gallery_theme' parameter is being used or manipulated.

Since the vulnerability requires authenticated attackers with Author-level access or higher to inject scripts, detection on the network level is challenging. Instead, detection should focus on scanning the WordPress installation for the plugin version and inspecting pages or posts that use the Envira Gallery shortcode for suspicious script injections.

• Check the installed Envira Gallery plugin version via WordPress admin or by running a command to list installed plugins, e.g., `wp plugin list | grep envira-gallery` using WP-CLI.
• Search the WordPress database for occurrences of the 'justified_gallery_theme' parameter or suspicious script tags in posts or pages, e.g., using SQL queries like: `SELECT ID, post_content FROM wp_posts WHERE post_content LIKE '%justified_gallery_theme%' OR post_content LIKE '%<script>%'`.
• Use security scanning tools or WordPress security plugins that can detect stored XSS vulnerabilities or anomalous content in posts.

Useful 0 Not Useful 0

What immediate steps should I take to mitigate this vulnerability?

To mitigate the Stored Cross-Site Scripting vulnerability in the Envira Gallery plugin, immediate steps include:

• Update the Envira Gallery plugin to a version later than 1.12.3 where the vulnerability is fixed.
• Restrict Author-level and higher user permissions to trusted users only, as exploitation requires authenticated users with such access.
• Review and sanitize any existing content or gallery configurations that use the 'justified_gallery_theme' parameter to remove any injected scripts.
• Implement Web Application Firewall (WAF) rules to detect and block attempts to inject malicious scripts via this parameter.
• Monitor logs and user activities for suspicious behavior related to gallery editing or shortcode usage.

Useful 0 Not Useful 0