CVE-2025-6065: Image Resizer On The Fly RCE Vulnerability

CVE-2025-6065 Overview

The Image Resizer On The Fly plugin for WordPress contains a critical arbitrary file deletion vulnerability due to insufficient file path validation in the delete task. This path traversal flaw (CWE-22) affects all versions up to and including version 1.1, allowing unauthenticated attackers to delete arbitrary files on the server. When critical files such as wp-config.php are deleted, this vulnerability can lead to remote code execution by forcing WordPress into a reinstallation state.

Critical Impact

Unauthenticated attackers can delete arbitrary files on WordPress servers, potentially leading to complete site compromise and remote code execution through strategic file deletion.

Affected Products

• Image Resizer On The Fly plugin for WordPress versions up to and including 1.1
• WordPress installations using the vulnerable plugin
• Any web server hosting affected WordPress sites

Discovery Timeline

• 2025-06-14 - CVE CVE-2025-6065 published to NVD
• 2025-06-16 - Last updated in NVD database

Technical Details for CVE-2025-6065

Vulnerability Analysis

This vulnerability represents a classic path traversal attack vector that enables arbitrary file deletion on affected WordPress installations. The delete task functionality within the Image Resizer On The Fly plugin fails to properly validate user-supplied file paths before performing file deletion operations. This lack of input sanitization allows attackers to escape the intended directory structure using directory traversal sequences (such as ../) to target files outside the plugin's working directory.

The attack can be executed remotely over the network without requiring any authentication, making it particularly dangerous for publicly accessible WordPress sites. The ability to delete arbitrary files has severe implications for both data integrity and system availability. When attackers delete critical configuration files like wp-config.php, WordPress enters an installation wizard state, potentially allowing attackers to reconfigure the site with malicious database credentials or inject backdoors during the reinstallation process.

Root Cause

The root cause is insufficient file path validation in the plugin's file handling routines. The vulnerable code at line 25 of image-resizer-on-the-fly.php accepts user-controlled input for file paths without proper sanitization or canonicalization. The plugin fails to implement security measures such as:

• Stripping or rejecting directory traversal sequences (../ or ..\)
• Validating that the target file resides within allowed directories
• Checking file path canonicalization to prevent path manipulation
• Implementing proper access controls for the delete functionality

Attack Vector

The vulnerability is exploited over the network by sending crafted HTTP requests to the WordPress installation. An unauthenticated attacker can manipulate the file path parameter in the delete task to traverse directories and target arbitrary files on the filesystem. The attack does not require any user interaction, allowing for automated exploitation.

Attackers typically target critical WordPress files such as:

• wp-config.php - Database credentials and security keys
• .htaccess - Apache configuration and security rules
• Plugin and theme files - To disable security plugins or modify site behavior
• Log files - To cover tracks after exploitation

Successful exploitation can chain into remote code execution by forcing WordPress into reinstallation mode or by deleting security mechanisms that would otherwise prevent further attacks. For detailed technical analysis, refer to the Wordfence Vulnerability Analysis.

Detection Methods for CVE-2025-6065

Indicators of Compromise

• Unexpected HTTP requests to plugin endpoints containing path traversal sequences (../)
• Missing critical WordPress files such as wp-config.php, .htaccess, or core plugin files
• WordPress sites unexpectedly entering installation wizard mode
• Web server error logs showing file not found errors for previously existing files
• Access logs containing requests to Image Resizer On The Fly plugin endpoints with suspicious parameters

Detection Strategies

• Monitor web server access logs for requests containing ../ or encoded variants (%2e%2e%2f) targeting plugin endpoints
• Implement file integrity monitoring to detect unauthorized deletion of critical WordPress files
• Deploy Web Application Firewall (WAF) rules to block path traversal patterns in requests to WordPress plugins
• Enable WordPress file change detection through security plugins like Wordfence
• Configure alerts for any modifications or deletions of wp-config.php and other critical files

Monitoring Recommendations

• Establish baseline file integrity checksums for critical WordPress files and monitor for unexpected changes
• Configure real-time alerting for file deletion events in WordPress directories
• Review web server logs regularly for suspicious activity patterns targeting the Image Resizer On The Fly plugin
• Monitor for WordPress sites unexpectedly entering setup/installation mode
• Track plugin-related HTTP requests for anomalous patterns or high-frequency access

How to Mitigate CVE-2025-6065

Immediate Actions Required

• Deactivate and remove the Image Resizer On The Fly plugin immediately if running version 1.1 or earlier
• Verify the integrity of critical WordPress files including wp-config.php, .htaccess, and core files
• Review web server access logs for evidence of exploitation attempts
• Implement WAF rules to block path traversal attacks targeting WordPress plugins
• Consider restoring from backup if file deletion is suspected

Patch Information

At the time of publication, users should check the WordPress Plugin Page for updated versions that address this vulnerability. Until a patched version is available, the plugin should be completely removed from WordPress installations. Administrators can review the vulnerable code section at the WordPress Plugin Source Code.

Workarounds

• Remove the Image Resizer On The Fly plugin entirely until a security patch is released
• Implement server-level file deletion restrictions for the WordPress uploads and plugin directories
• Deploy WAF rules to block requests containing path traversal sequences to WordPress plugin endpoints
• Use server-level access controls to restrict write/delete permissions for the web server user
• Enable WordPress audit logging to track file system operations

# Configuration example - Apache mod_rewrite rule to block path traversal attempts
# Add to .htaccess in WordPress root directory
RewriteEngine On
RewriteCond %{QUERY_STRING} (\.\./|\.\.\\) [NC,OR]
RewriteCond %{REQUEST_URI} (\.\./|\.\.\\) [NC]
RewriteRule .* - [F,L]

# Block direct access to the vulnerable plugin endpoint
RewriteRule ^wp-content/plugins/image-resizer-on-the-fly/.* - [F,L]