CVE-2026-66474 Overview
CVE-2026-66474 is an unauthenticated Cross-Site Request Forgery (CSRF) vulnerability affecting the Insert Headers and Footers Code – HT Script WordPress plugin in versions up to and including 1.1.8. The flaw is classified under CWE-352 and allows an attacker to induce an authenticated administrator to perform unintended state-changing actions in the plugin. Exploitation requires user interaction, typically by tricking a logged-in administrator into visiting a crafted page. The vulnerability affects the integrity of plugin configuration, which stores custom header and footer scripts injected across the WordPress site.
Critical Impact
An attacker can leverage CSRF to alter header and footer script configuration in the plugin, potentially enabling persistent injection of attacker-controlled content across site pages when an administrator is deceived into triggering the request.
Affected Products
- Insert Headers and Footers Code – HT Script WordPress plugin, versions <= 1.1.8
Discovery Timeline
- 2026-07-27 - CVE-2026-66474 published to NVD
- 2026-07-27 - Last updated in NVD database
Technical Details for CVE-2026-66474
Vulnerability Analysis
The Insert Headers and Footers Code – HT Script plugin manages custom script injection into the <head> and footer sections of a WordPress site. The affected versions do not validate the origin of state-changing HTTP requests to the plugin's configuration endpoints. As a result, requests reaching administrative functionality lack a verified anti-CSRF token or equivalent origin check.
An attacker hosts a page containing a forged form or automatic request targeting the plugin. When a logged-in WordPress administrator visits that page, the browser submits the authenticated request using the administrator's session cookies. The plugin processes the request as legitimate and applies the attacker-supplied configuration.
Because the plugin's purpose is to inject arbitrary scripts into rendered pages, a successful CSRF write can enable persistent script injection affecting all site visitors. The vulnerability carries limited integrity impact per its CVSS metrics and no direct confidentiality or availability impact, but the downstream effect of injected scripts can extend the attack surface.
Root Cause
The root cause is the absence of a proper CSRF protection mechanism on the plugin's administrative request handlers. WordPress provides a nonce API (wp_nonce_field, check_admin_referer, wp_verify_nonce) intended to protect such handlers. Insert Headers and Footers Code – HT Script <= 1.1.8 either omits nonce validation or applies it inconsistently on endpoints that modify stored script content.
Attack Vector
The attack occurs over the network and requires user interaction. An attacker crafts a malicious HTML page containing an auto-submitting form or fetch request pointed at the vulnerable plugin endpoint on the target WordPress site. The attacker then delivers the link to a site administrator through phishing, social media, or a compromised third-party site. When the administrator loads the page while authenticated to the target WordPress instance, the browser transmits the forged request with valid session cookies, and the plugin applies the change.
See the Patchstack CSRF Vulnerability Report for the advisory record.
Detection Methods for CVE-2026-66474
Indicators of Compromise
- Unexpected modifications to header or footer script settings stored by the Insert Headers and Footers Code – HT Script plugin.
- Presence of unfamiliar <script> tags, remote script src values, or obfuscated JavaScript in the plugin's saved header/footer content.
- WordPress access log entries showing POST requests to the plugin's admin endpoints with Referer headers pointing to external, untrusted domains.
Detection Strategies
- Compare current plugin option values against a known-good baseline stored in backups or version control.
- Monitor the WordPress options table for changes to plugin-specific keys outside expected administrative maintenance windows.
- Alert on administrator-authenticated POST requests to plugin admin URLs where the Referer or Origin header does not match the site's own hostname.
Monitoring Recommendations
- Enable and centralize WordPress admin activity logging using a plugin such as WP Activity Log or an equivalent audit trail solution.
- Ingest web server access logs into a SIEM or data lake to correlate administrator sessions with suspicious cross-origin requests.
- Track outbound requests from site visitors to unexpected script hosts, which may indicate injected header or footer scripts are active.
How to Mitigate CVE-2026-66474
Immediate Actions Required
- Update the Insert Headers and Footers Code – HT Script plugin to a version later than 1.1.8 once the vendor publishes a fixed release.
- Audit the current header and footer script configuration for unauthorized entries and remove any unrecognized content.
- Rotate administrator credentials and invalidate active sessions if unauthorized configuration changes are found.
Patch Information
At the time of publication, the advisory identifies all versions <= 1.1.8 as affected. Administrators should consult the Patchstack advisory and the plugin's WordPress.org listing for the fixed release version.
Workarounds
- Deactivate the Insert Headers and Footers Code – HT Script plugin until a patched version is available if header and footer scripts can be managed by alternative means.
- Restrict WordPress administrator access to trusted networks using IP allowlisting at the web server or WAF layer.
- Require administrators to use isolated browser profiles or dedicated browsers when accessing the WordPress admin panel to limit the impact of cross-site requests.
- Deploy a Web Application Firewall rule that enforces same-origin Referer or Origin headers on POST requests to /wp-admin/ endpoints associated with the plugin.
Disclaimer: This content was generated using AI. While we strive for accuracy, please verify critical information with official sources.
