CVE-2024-10932: Backup Migration Plugin RCE Vulnerability

CVE-2024-10932 Overview

CVE-2024-10932 affects the Backup Migration plugin for WordPress in all versions up to and including 1.4.6. The vulnerability stems from insecure deserialization of untrusted input within the recursive_unserialize_replace function. Unauthenticated attackers can inject a PHP object into the application. When combined with a Property-Oriented Programming (POP) chain, the flaw allows arbitrary file deletion, sensitive data retrieval, or code execution. Exploitation requires that a WordPress administrator first create a staging site, which acts as a trigger condition. The flaw is classified as Deserialization of Untrusted Data [CWE-502].

Critical Impact

Unauthenticated attackers can achieve PHP Object Injection leading to arbitrary file deletion, data disclosure, or remote code execution on affected WordPress installations.

Affected Products

• WordPress Backup Migration plugin versions up to and including 1.4.6
• WordPress sites with the plugin installed and an administrator-created staging site
• Hosting environments running vulnerable versions of the backup-backup plugin

Discovery Timeline

• 2025-01-04 - CVE-2024-10932 published to NVD
• 2026-04-15 - Last updated in NVD database

Technical Details for CVE-2024-10932

Vulnerability Analysis

The Backup Migration plugin processes serialized PHP data through the recursive_unserialize_replace function located in includes/database/search-replace.php. This function deserializes user-controllable input without validating its origin or contents. PHP's native unserialize() reconstructs objects from a string representation and invokes magic methods such as __wakeup or __destruct during instantiation. Attackers can craft a serialized payload that instantiates arbitrary classes available within the WordPress runtime. When a suitable POP chain exists across loaded plugins, themes, or core code, the deserialization triggers method calls that operate on attacker-controlled properties.

Root Cause

The root cause is unsafe deserialization of untrusted input. The plugin trusts serialized data passed through the search-and-replace routine used during staging-site creation. No type validation, allow-listing, or signature verification precedes the call to unserialize(), enabling object injection.

Attack Vector

The attack is delivered over the network and requires user interaction in the form of an administrator initiating a staging site operation. Once the staging workflow runs, attacker-supplied serialized data reaches the vulnerable function and is deserialized. A working POP chain extends the impact from object instantiation to arbitrary file deletion, file read primitives, or remote code execution within the web server context.

No verified public exploit code is available. Refer to the Wordfence Vulnerability Report and the WordPress Plugin Source Code for technical details of the vulnerable code path.

Detection Methods for CVE-2024-10932

Indicators of Compromise

• Unexpected staging site creation events in WordPress administrative logs
• Outbound HTTP requests originating from the web server to attacker-controlled hosts following staging operations
• Unexplained creation, modification, or deletion of files under the WordPress installation directory
• PHP error log entries referencing unserialize() failures or unknown class instantiations during plugin operation

Detection Strategies

• Inspect HTTP POST bodies and database fields processed by recursive_unserialize_replace for serialized object markers such as O: and C: patterns
• Monitor calls to unserialize() through PHP runtime instrumentation or Web Application Firewall (WAF) rules targeting PHP Object Injection signatures
• Correlate staging site creation events with subsequent file system writes outside the staging directory
• Audit installed plugin versions across managed WordPress sites and flag instances of backup-backup at version 1.4.6 or earlier

Monitoring Recommendations

• Enable WordPress audit logging for plugin activation, staging operations, and administrator account activity
• Forward web server, PHP-FPM, and WordPress logs to a centralized analytics platform for correlation
• Alert on PHP processes spawning shell binaries such as sh, bash, php -r, or network utilities like curl and wget
• Track changes to wp-config.php, .htaccess, and files under wp-content/uploads/ for unauthorized modifications

How to Mitigate CVE-2024-10932

Immediate Actions Required

• Update the Backup Migration plugin to version 1.4.6.1 or later on every WordPress installation
• Restrict administrator access to the staging site functionality until the patch is verified in production
• Review WordPress administrator accounts and rotate credentials for any account that may have triggered staging operations
• Scan the file system for unauthorized files, web shells, or modifications introduced after the plugin was installed

Patch Information

The vendor addressed the vulnerability in Backup Migration version 1.4.6.1. The patched code is available in the WordPress Plugin Code Review. Apply the update through the WordPress plugin management interface or by deploying the updated package across managed sites.

Workarounds

• Deactivate and remove the Backup Migration plugin until the patched version can be deployed
• Block external access to staging site initiation endpoints using a WAF or reverse proxy rule
• Limit plugin file modifications by enforcing read-only permissions on wp-content/plugins/backup-backup/
• Disable PHP object deserialization at the application boundary using a WAF signature for serialized payloads in untrusted parameters

# Update the Backup Migration plugin using WP-CLI
wp plugin update backup-backup --version=1.4.6.1

# Verify the installed version after upgrade
wp plugin get backup-backup --field=version

# Temporary mitigation: deactivate the plugin until patched
wp plugin deactivate backup-backup