CVE-2025-39426 Overview
CVE-2025-39426 is a Cross-Site Request Forgery (CSRF) vulnerability affecting the illow – Cookies Consent WordPress plugin, also known as lgpd-compliant-cookie-banner. The flaw affects all plugin versions up to and including 0.2.0. The vulnerability is classified under [CWE-352] and stems from missing CSRF protections on state-changing plugin actions. An attacker can trick an authenticated administrator into submitting forged requests that modify plugin configuration without consent.
Critical Impact
An attacker who convinces a logged-in administrator to visit a malicious page can alter cookie consent banner settings, potentially breaking compliance with LGPD and GDPR requirements on the target site.
Affected Products
- illow – Cookies Consent WordPress plugin (lgpd-compliant-cookie-banner)
- All versions from n/a through 0.2.0
- WordPress sites using the affected plugin for LGPD-compliant cookie consent
Discovery Timeline
- 2025-04-17 - CVE-2025-39426 published to NVD
- 2026-06-17 - Last updated in NVD database
Technical Details for CVE-2025-39426
Vulnerability Analysis
The illow – Cookies Consent plugin fails to validate the origin of state-changing HTTP requests. WordPress provides the wp_nonce_field() and check_admin_referer() functions to defend against CSRF, but the plugin does not enforce these checks on affected endpoints. An attacker abuses the trust the site places in an authenticated user's browser session. When an administrator visits an attacker-controlled page while logged into WordPress, the browser automatically forwards session cookies with the forged request.
Successful exploitation impacts integrity only. Confidentiality and availability are not directly affected. The scope remains unchanged, meaning the impact is contained to the vulnerable plugin's data. User interaction is required, which limits the attack to social engineering scenarios such as phishing links or embedded iframes.
Root Cause
The root cause is the absence of anti-CSRF tokens on plugin request handlers. Without nonce verification, the plugin cannot distinguish between a legitimate administrator action and a forged cross-site request. This is a classic [CWE-352] weakness in web applications that rely solely on ambient authentication cookies.
Attack Vector
Exploitation requires network access to trigger a request against the target WordPress site. The attacker crafts a malicious HTML page containing an auto-submitting form or image tag pointing at the vulnerable plugin endpoint. When an authenticated administrator loads the attacker's page, the browser issues the request with valid session cookies. The plugin processes the action as if it came from the administrator. See the Patchstack Vulnerability Report for additional technical detail.
Detection Methods for CVE-2025-39426
Indicators of Compromise
- Unexpected modifications to cookie consent banner configuration in the WordPress admin interface
- HTTP POST requests to plugin endpoints with Referer headers pointing to external domains
- Administrator sessions producing plugin configuration changes shortly after visiting untrusted URLs
- Absence of _wpnonce or _wp_http_referer parameters in plugin request logs
Detection Strategies
- Review WordPress audit logs for configuration changes to the lgpd-compliant-cookie-banner plugin that lack a matching administrator workflow
- Inspect web server access logs for cross-origin Referer values on plugin admin URLs
- Correlate administrator browsing activity with plugin settings changes to identify forged requests
Monitoring Recommendations
- Enable a WordPress activity logging plugin to record plugin option changes with timestamps and user attribution
- Alert on outbound HTTP requests from administrator browsers to newly registered domains during active admin sessions
- Monitor plugin version inventory and flag installations running lgpd-compliant-cookie-banner at version 0.2.0 or earlier
How to Mitigate CVE-2025-39426
Immediate Actions Required
- Deactivate the illow – Cookies Consent plugin if no patched version is installed on the site
- Restrict WordPress administrator accounts to dedicated browser profiles that do not browse untrusted content
- Enforce short session lifetimes for WordPress administrators to reduce the CSRF exposure window
- Audit recent cookie consent banner configuration changes for signs of tampering
Patch Information
At the time of publication, the NVD entry lists affected versions through 0.2.0 with no fixed version identified. Site owners should consult the Patchstack Vulnerability Report for updated fix availability and upgrade to a patched release once published by the vendor.
Workarounds
- Deploy a web application firewall rule that requires a same-origin Referer header on plugin admin endpoints
- Replace the plugin with an alternative cookie consent solution that implements WordPress nonce protections
- Require administrators to log out of WordPress before browsing external sites, or use a separate browser for admin work
- Apply the WordPress SameSite=Strict cookie attribute where feasible to block cross-site cookie transmission
Disclaimer: This content was generated using AI. While we strive for accuracy, please verify critical information with official sources.
