CVE-2026-6101: AMP for WP Arbitrary File Write and RCE Vulnerability

Technical summary

CVE-2026-6101 is an arbitrary file write vulnerability in the AMP for WP plugin's ampforwp_save_local_font() function. The vulnerability stems from two implementation gaps: unsafe ZIP file extraction that follows directory traversal paths without validation, and inadequate cleanup that leaves nested directories and files on the filesystem. The flaw requires authenticated access at Author level or above, but once triggered, permits writing files to web-accessible locations. The CVSS 3.1 score of 7.5 (HIGH) reflects high confidentiality, integrity, and availability impact, mitigated by the requirement for local authentication and complex attack conditions.

Business impact

Compromise of a WordPress site hosting this plugin could result in complete site takeover, data theft, malware distribution, or use of the server for further attacks. Organizations relying on AMP for WP for mobile optimization should assume that a compromised instance exposes sensitive content, user data, and server infrastructure. The threat is elevated if the vulnerable plugin is deployed across multiple WordPress instances or if the uploads directory is web-accessible and PHP-executable—a common configuration.

Affected systems

The AMP for WP – Accelerated Mobile Pages plugin is affected in versions up to and including 1.1.12. Any WordPress installation running this plugin at or below this version, particularly those with multiple Author-level or Administrator users, is potentially vulnerable. The risk is highest on shared hosting environments where the uploads directory is world-readable and executable, or on sites where user account management is permissive.

Exploitability

Exploitation requires valid WordPress credentials with at least Author-level privileges. The attack is not wormable or remotely exploitable without authentication. The complexity is rated as high in the CVSS vector, reflecting the need for an authenticated user and specific server configuration (PHP execution in uploads). However, for organizations with many content editors or authors, or those with permissive account provisioning, the practical likelihood of exploitation increases.

Remediation

Update the AMP for WP plugin to a patched version released after 1.1.12. Verify the patch version against the official WordPress plugin repository or the vendor's advisory. Additionally, implement server-level mitigations: disable PHP execution in the wp-content/uploads directory via .htaccess, nginx configuration, or web server settings; restrict Author-level permissions to trusted users only; and audit existing uploads for malicious files.

Patch guidance

Check the WordPress plugin repository for AMP for WP or the vendor's security advisory for the patched version number. Apply the update immediately in a staging environment to verify compatibility with your theme and other plugins, then deploy to production. If a patch is not yet available, temporarily disable the plugin until an update is released. Verify by checking the plugin version in the WordPress dashboard under Plugins.

Detection guidance

Monitor file access logs for unexpected PHP files created in wp-content/uploads or subdirectories, especially with timestamps coinciding with plugin updates or after Author-level account activity. Search the uploads directory for .php, .phtml, or .phar files. Review WordPress audit logs or security plugins for ZIP extraction or file write operations initiated by non-administrator users. Inspect the ampforwp_save_local_font() function calls in access logs or WAF logs.

Why prioritize this

Although this vulnerability requires authentication and complex conditions, it enables remote code execution on a widely-used WordPress plugin. The impact is severe for any organization using AMP for WP, particularly those with less restrictive user role management. The ease of exploitation once conditions are met, combined with the plugin's popularity, warrants prompt patching. Enterprises with centralized WordPress deployments should prioritize inventory and remediation across all instances.

Risk score, explained

The CVSS 3.1 score of 7.5 (HIGH) appropriately reflects the combination of high confidentiality, integrity, and availability impact (remote code execution potential) against the mitigating factors of required authentication and high complexity. For organizations where Author-level accounts are common and uploads directory execution is enabled, the practical risk may exceed the base score; conversely, organizations with strict access controls and hardened server configurations face lower risk. Context-dependent assessment is essential.

Frequently asked questions