elFinder MySQL has a SQL Injection in its Volume Driver (elFinderVolumeMySQL)

Summary

An authenticated SQL injection vulnerability in the elFinder MySQL volume driver (elFinderVolumeMySQL) allows any logged-in user, including users with read-only access to the affected volume, to inject SQL through a crafted target file hash. Successful exploitation can lead to unauthorized data disclosure and denial of service.

This vulnerability only affects installations configured to use the MySQL volume driver. Installations using the default LocalFileSystem driver are not affected.

Description

A vulnerability in elFinder's MySQL volume driver (elFinderVolumeMySQL) allows authenticated SQL injection through a crafted file hash passed via the target parameter.

The issue is caused by two behaviors working together:

1. File hashes are decoded without validating that the decoded value is a valid MySQL object identifier.
2. The decoded value is then used in MySQL driver queries, including cacheDir(), _joinPath(), _stat(), and _fopen().

Because the MySQL storage schema uses numeric id and parent_id values, an authenticated user can supply a crafted hash that alters the intended SQL query logic. Successful exploitation can lead to unauthorized data disclosure and denial of service. The extent of impact depends on the privileges granted to the configured MySQL account.

This vulnerability only affects installations configured to use the MySQL volume driver. Installations using the default LocalFileSystem driver are not affected.

Impact

An authenticated user, including a user with read-only access to the affected volume, can exploit this issue to:

• disclose data accessible to the configured MySQL account, including file contents stored by the driver and database metadata
• trigger denial of service through expensive or unexpectedly broad query results that can lead to excessive memory consumption

The severity of data exposure depends on the privileges granted to the configured MySQL account.