Attack Surface: Unauthenticated Web UI Access
Description: Flink Web UI is accessible without authentication.
Flink Contribution: Flink provides the Web UI, which if not secured, allows unauthorized access.
Example: Attacker accesses the Web UI and cancels jobs or views sensitive cluster information.
Impact: Data processing disruption, information disclosure, cluster manipulation.
Risk Severity: High
Mitigation Strategies:
- Developers/Users: Enable Flink Web UI authentication (e.g., basic, Kerberos). Restrict network access to the Web UI.
Attack Surface: Deserialization Vulnerabilities in RPC Communication
Description: Flink's internal RPC uses deserialization, which can be exploited for remote code execution.
Flink Contribution: Flink's core communication relies on RPC and potentially vulnerable deserialization.
Example: Malicious serialized payload sent to JobManager leads to code execution on the server.
Impact: Remote Code Execution, full cluster compromise.
Risk Severity: Critical
Mitigation Strategies:
- Developers/Users: Keep Flink updated to patched versions. Restrict deserialization classes if possible. Monitor Flink security advisories.
Attack Surface: Malicious Job JAR Submission
Description: Submitting malicious JARs to Flink for execution.
Flink Contribution: Flink's job submission mechanism allows execution of user-provided code in JARs.
Example: Malicious JAR establishes reverse shell from TaskManager, compromising the host.
Impact: Remote Code Execution, data theft, cluster compromise.
Risk Severity: High
Mitigation Strategies:
- Developers/Users: Implement strict access control for job submission. Vet JARs before deployment (code review, security scans). Consider code signing and sandboxing.
Attack Surface: Injection through Job Parameters and Configurations
Description: Injecting malicious code via job parameters processed by Flink or UDFs.
Flink Contribution: Flink allows job configuration through parameters, which can be misused if not handled securely in Flink internals or user code.
Example: Job parameter used in UDF to execute system commands, leading to command injection.
Impact: Command Injection, Remote Code Execution, data manipulation.
Risk Severity: High
Mitigation Strategies:
- Developers: Sanitize and validate job parameters in UDFs and Flink job setup. Avoid executing user-provided strings as commands.
- Users: Sanitize inputs to Flink jobs, especially from untrusted sources.
Attack Surface: Unauthenticated REST API Access
Description: Flink REST API is accessible without authentication.
Flink Contribution: Flink provides the REST API, which if unsecured, allows unauthorized cluster interaction.
Example: Attacker uses REST API to submit malicious jobs or retrieve cluster information.
Impact: Data processing disruption, information disclosure, cluster manipulation, potential RCE via API vulnerabilities.
Risk Severity: High
Mitigation Strategies:
- Developers/Users: Enable Flink REST API authentication (e.g., API keys, OAuth 2.0). Restrict network access to the REST API.
Attack Surface: Connector Vulnerabilities (High/Critical Impact)
Description: Vulnerabilities in Flink connector code leading to severe impact.
Flink Contribution: Flink relies on connectors; vulnerabilities in these can be exploited within the Flink context.
Example: Vulnerability in a connector allows remote code execution upon processing specific data.
Impact: Data breaches, denial of service, remote code execution, external system compromise.
Risk Severity: High (when impact is severe like RCE)
Mitigation Strategies:
- Developers/Users: Use official, updated connectors. Review third-party connectors. Monitor connector security advisories.