CVE-2023-39265: Apache Superset Information Disclosure

CVE-2023-39265 Overview

Apache Superset contains an improper input validation vulnerability that allows SQLite database connections to be incorrectly registered when an attacker uses alternative driver names like sqlite+pysqlite or by using database imports. This security flaw could allow for unexpected file creation on Superset webservers. Additionally, if Apache Superset is using a SQLite database for its metadata (not advised for production use), it could result in more severe vulnerabilities related to confidentiality and integrity.

Critical Impact

This vulnerability enables attackers to bypass database connection restrictions, potentially leading to unauthorized file creation and, in misconfigured environments using SQLite for metadata storage, could result in data exfiltration or integrity compromise.

Affected Products

• Apache Superset versions up to and including 2.1.0
• Apache Superset instances configured with SQLite metadata databases (increased severity)
• Apache Superset deployments allowing user-configured database connections

Discovery Timeline

• 2023-09-06 - CVE-2023-39265 published to NVD
• 2024-11-21 - Last updated in NVD database

Technical Details for CVE-2023-39265

Vulnerability Analysis

This vulnerability stems from insufficient validation of database connection strings in Apache Superset's database registration functionality. The application fails to properly validate and restrict SQLite driver names, allowing attackers to bypass security controls intended to prevent SQLite connections. The improper input validation (CWE-20) allows malicious actors to register SQLite databases using alternative driver naming conventions that evade the application's denylist filters.

When a user attempts to create a database connection, Superset should block SQLite connections for security reasons. However, the validation logic can be circumvented by specifying alternative SQLAlchemy dialect names such as sqlite+pysqlite instead of the standard sqlite driver. Additionally, attackers can leverage database import functionality to achieve the same unauthorized access.

Root Cause

The root cause lies in incomplete input validation within the database connection registration process. Apache Superset implements a denylist approach to block certain database types, but this implementation does not account for all valid SQLAlchemy dialect variations. SQLAlchemy supports multiple ways to specify the same database backend, and the denylist only covers a subset of these naming conventions.

The vulnerability is further exacerbated in environments where Apache Superset uses SQLite for its own metadata storage—a configuration explicitly discouraged for production deployments. In such scenarios, attackers could potentially access or modify the application's internal data, escalating the impact from file creation to full data compromise.

Attack Vector

The attack can be executed remotely over the network by authenticated users with database connection creation privileges. The exploitation process involves:

1. An attacker with sufficient privileges accesses the database connection configuration interface
2. Instead of using the blocked sqlite:/// connection string, the attacker specifies sqlite+pysqlite:///path/to/database.db
3. Superset's validation logic fails to recognize this as a SQLite connection attempt
4. The connection is registered successfully, allowing the attacker to create arbitrary files on the webserver
5. If the Superset instance uses SQLite for metadata, the attacker can potentially query or modify internal application data

The vulnerability requires network access but does not require user interaction. It can be exploited by users with permissions to configure database connections, making privilege management a critical control factor.

Detection Methods for CVE-2023-39265

Indicators of Compromise

• Presence of unexpected SQLite database files created in web server directories
• Database connection configurations containing sqlite+pysqlite or similar alternative driver strings
• Unusual database import activities in Apache Superset audit logs
• Queries or connections to the Superset metadata database from unexpected sources
• New database connections registered with file-based connection strings

Detection Strategies

• Monitor Apache Superset configuration changes for database connection registrations containing SQLite-related strings
• Implement file integrity monitoring on Superset webserver directories to detect unexpected file creation
• Review application logs for database connection attempts using alternative dialect naming conventions
• Audit user permissions to identify accounts with database connection creation capabilities

Monitoring Recommendations

• Enable comprehensive audit logging for all database connection creation and modification events
• Configure alerts for any database connection strings containing sqlite, pysqlite, or file path patterns
• Monitor for suspicious file system activity on Superset webservers, particularly new .db or .sqlite file creation
• Implement regular reviews of registered database connections to identify unauthorized entries

How to Mitigate CVE-2023-39265

Immediate Actions Required

• Upgrade Apache Superset to a version newer than 2.1.0 that contains the security fix
• Audit all existing database connections for unauthorized SQLite registrations and remove any suspicious entries
• Review and restrict user permissions for database connection creation capabilities
• Ensure Apache Superset is not using SQLite for metadata storage in production environments
• Implement network segmentation to limit access to the Superset administration interface

Patch Information

The Apache Software Foundation has addressed this vulnerability in versions after 2.1.0. Organizations should consult the Apache Developer Mailing List for official security advisories and upgrade instructions. Additional technical details regarding exploitation can be found in the Packet Storm RCE Exploit reference.

Workarounds

• Restrict database connection creation permissions to only trusted administrators
• Implement additional network-level controls to limit access to Superset's administrative functions
• Deploy a web application firewall (WAF) with rules to block requests containing SQLite-related connection strings
• If upgrading is not immediately possible, manually modify the database connection denylist to include all SQLite dialect variations

# Configuration example - Review and remove unauthorized database connections
# Check for SQLite connections in Superset database
superset fab list-databases | grep -i sqlite

# Restrict permissions for database creation
# In superset_config.py, ensure proper role-based access controls
PREVENT_UNSAFE_DB_CONNECTIONS = True