CVE-2025-25091 Overview
CVE-2025-25091 is a stored cross-site scripting (XSS) vulnerability in the zackdesign NextGen Cooliris Gallery plugin for WordPress. The flaw affects all plugin versions up to and including 0.7. The plugin fails to properly neutralize user-supplied input before it is rendered within web pages, allowing an authenticated attacker to persist malicious script content. When another user loads the affected page, the script executes in their browser session. The vulnerability is categorized under [CWE-79], improper neutralization of input during web page generation.
Critical Impact
An authenticated attacker with low privileges can inject persistent JavaScript that executes in the context of any user visiting the affected gallery page, enabling session theft, redirection, or unauthorized actions.
Affected Products
- zackdesign NextGen Cooliris Gallery WordPress plugin, all versions up to and including 0.7
- WordPress installations that have the NextGen Cooliris Gallery plugin activated
- Sites depending on this plugin for NextGen gallery integration
Discovery Timeline
- 2025-02-07 - CVE-2025-25091 published to the National Vulnerability Database
- 2026-06-17 - Last updated in NVD database
Technical Details for CVE-2025-25091
Vulnerability Analysis
The vulnerability resides in how NextGen Cooliris Gallery handles user-controlled input during page generation. The plugin renders values without applying output encoding or input sanitization suitable for an HTML context. As a result, attacker-supplied HTML and JavaScript payloads are stored and later served to visitors as executable content. Because the injected script executes in the security context of the WordPress site, an attacker can pivot to session hijacking, forced browsing actions, credential harvesting through fake forms, or client-side redirection to attacker-controlled infrastructure. The stored nature of this XSS increases impact because the payload persists in the database and affects every user rendering the affected page.
Root Cause
The root cause is missing or insufficient input validation and output encoding in the plugin code paths that accept and later render user input. The plugin does not enforce escaping functions such as esc_html(), esc_attr(), or wp_kses() before writing values into the HTML response, which permits arbitrary tags and event handlers to be injected.
Attack Vector
Exploitation requires an authenticated user with at least contributor-level privileges and user interaction from a victim who visits the affected gallery page. The attacker submits a payload through a plugin field that lacks sanitization. The malicious script is stored server-side and executes in the browser of any subsequent viewer, including administrators. Because the scope changes across security boundaries, the impact reaches users beyond the attacker's own session.
No verified proof-of-concept code has been published. Refer to the Patchstack Vulnerability Report for additional technical context.
Detection Methods for CVE-2025-25091
Indicators of Compromise
- Unexpected <script> tags, javascript: URIs, or DOM event handler attributes (onerror, onload, onclick) stored in NextGen gallery metadata within the WordPress database
- Outbound browser requests from admin sessions to unfamiliar external domains after visiting gallery pages
- New or modified administrator accounts created shortly after gallery pages were accessed
- Suspicious entries in wp_posts, wp_postmeta, or plugin-specific tables containing encoded HTML payloads
Detection Strategies
- Audit stored plugin data for HTML tags and JavaScript keywords using database queries against post meta and plugin tables
- Inspect HTTP responses served by gallery pages for reflected untrusted content that lacks encoding
- Correlate contributor or editor account activity with subsequent administrator session anomalies
Monitoring Recommendations
- Enable WordPress audit logging for content creation and plugin option changes
- Deploy a web application firewall rule set that inspects POST payloads to plugin endpoints for XSS signatures
- Monitor browser telemetry from privileged users for anomalous script execution or unusual outbound connections
How to Mitigate CVE-2025-25091
Immediate Actions Required
- Deactivate and remove the NextGen Cooliris Gallery plugin until a patched release is confirmed available
- Review all contributor, author, and editor accounts and revoke unnecessary privileges
- Sanitize stored gallery data by inspecting and cleaning suspicious HTML content in the database
- Rotate administrator session cookies and reset passwords for accounts that accessed affected pages
Patch Information
No fixed version has been published in the referenced advisory at time of writing. All versions through 0.7 are affected. Monitor the Patchstack Vulnerability Report and the plugin repository for a security release.
Workarounds
- Uninstall the plugin and use an actively maintained gallery alternative
- Restrict user registration and limit low-privilege roles from submitting content that reaches gallery fields
- Deploy a WAF with rules that block HTML tags and script content in plugin request parameters
- Enforce a strict Content Security Policy (CSP) that disallows inline scripts to reduce exploitation impact
# Example: Content Security Policy header to limit inline script execution
Header set Content-Security-Policy "default-src 'self'; script-src 'self'; object-src 'none'; base-uri 'self'"
Disclaimer: This content was generated using AI. While we strive for accuracy, please verify critical information with official sources.
