Appsmith SQL Injection Vulnerability in FilterDataService

A SQL injection vulnerability has been identified in Appsmith’s FilterDataServiceCE.java, specifically within the dropTable method. This flaw affects Appsmith server instances running versions 1.98 and earlier of the interfaces package. The vulnerability stems from the direct concatenation of user-supplied table names into a SQL DROP TABLE statement without proper sanitization or validation. If an attacker can control the tableName argument, they can inject arbitrary SQL commands, potentially leading to unauthorized data manipulation, exfiltration, or data loss. This is particularly concerning in scenarios where the dropTable function is exposed through an API or utility accessible to users.

Attack Chain

1. The attacker identifies an Appsmith instance running a vulnerable version (<= 1.98) of the interfaces package.
2. The attacker discovers an endpoint or API that utilizes the FilterDataServiceCE.java’s dropTable method.
3. The attacker crafts a malicious tableName input containing SQL injection payload. Example: valid_table; DROP TABLE users; --.
4. The malicious input is passed to the dropTable method within FilterDataServiceCE.java.
5. The dropTable method concatenates the unsanitized input into a SQL DROP TABLE statement.
6. The resulting SQL query, containing the injected commands, is executed against the database via the executeDbQuery method.
7. The injected SQL commands are executed, potentially dropping tables, modifying data, or exfiltrating sensitive information, depending on the attacker’s payload and the database user’s permissions.
8. The attacker achieves their objective, such as data loss through arbitrary table deletion.

Impact

Successful exploitation of this SQL injection vulnerability can have severe consequences. The primary impact is data loss, as attackers can arbitrarily drop tables within the database. Depending on the database user’s privileges, attackers may also be able to exfiltrate sensitive data or modify existing data. The vulnerability affects Appsmith server instances. The number of affected instances is currently unknown. However, the potential impact includes unauthorized access to and manipulation of sensitive data, impacting the confidentiality, integrity, and availability of the Appsmith application and its underlying database.

Recommendation

• Upgrade Appsmith interfaces package to a version greater than 1.98 to patch the SQL injection vulnerability in FilterDataServiceCE.java.
• Implement input validation and sanitization on any endpoints or APIs that utilize the dropTable method to prevent SQL injection attacks.
• Deploy the provided Sigma rule to detect attempts to exploit this SQL injection vulnerability by monitoring for suspicious table names in logs associated with database operations.