attack-surface.md

Attack Surface Analysis for uber-go/zap

Attack Surface: Information Disclosure through Verbose or Debug Logging

Description: Sensitive information is unintentionally exposed in application logs due to overly verbose logging levels being enabled, a configuration choice facilitated by zap.

Zap Contribution: zap's ease of configuration and use of different logging levels (Debug, Info, Warn, Error, DPanic, Panic, Fatal) makes it simple to enable very detailed logging. If developers mistakenly leave debug or verbose levels active in production, sensitive data can be logged.

Example: An application is deployed to production with DebugLevel enabled in the zap configuration. As a result, every HTTP request header, including authorization tokens and session IDs, is logged. These logs are then stored in a location accessible to unauthorized personnel.

Impact:

• Exposure of sensitive data like API keys, session tokens, passwords, personal identifiable information (PII), and internal system details.
• Potential data breaches and compliance violations.

Risk Severity: High

Mitigation Strategies:

• Enforce Production Logging Level: Strictly configure zap to use appropriate logging levels (e.g., InfoLevel, WarnLevel, ErrorLevel) in production environments. Disable DebugLevel and VerboseLevel in production.
• Environment-Specific Configuration: Utilize environment variables or separate configuration files to manage logging levels for different environments (development, staging, production).
• Regular Log Audits: Periodically review production logs to identify and eliminate any unintentional logging of sensitive information, regardless of the configured level.

Attack Surface: Misconfigured Log Output Destinations (Sinks)

Description: Log output destinations (sinks) configured within zap are insecurely configured, leading to unauthorized access or data leakage. This is a direct consequence of zap's flexible sink configuration.

Zap Contribution: zap allows configuration of various sinks, including files, network connections, and custom implementations. Misconfiguration of these sinks, a feature of zap, can directly lead to security vulnerabilities.

Example:

• Unencrypted Network Sink: zap is configured to send logs over plain TCP to a remote server without TLS encryption. This exposes log data in transit to network eavesdropping, potentially revealing sensitive information contained within the logs.
• World-Readable File Sink: zap is configured to write log files to a directory with world-readable permissions (e.g., due to incorrect path configuration or permissions settings during deployment). This allows any user on the system to access potentially sensitive log data.

Impact:

• Information Disclosure: Unauthorized access to sensitive log data by eavesdroppers or local users.
• Data Breach: Leakage of sensitive information to unintended parties.

Risk Severity: High

Mitigation Strategies:

• Secure Network Sinks: Always use encrypted protocols (e.g., TLS/HTTPS for HTTP sinks, TLS for TCP sinks) when configuring zap to log to network destinations.
• Restrict File Permissions: Ensure log files are written to directories with restricted access permissions. Limit access to only necessary users and processes.
• Sink Validation and Testing: Thoroughly review and test the configuration of all zap sinks to ensure they are secure and meet security requirements.

Attack Surface: Dependency Vulnerabilities in zap or its Dependencies

Description: Security vulnerabilities are present in zap itself or in its dependencies. While not a vulnerability in zap's code directly in many cases, the application's reliance on zap makes it vulnerable.

Zap Contribution: Like any software library, zap depends on other packages. Vulnerabilities in these dependencies, or even in zap itself, can be exploited in applications using zap. This is an indirect attack surface introduced by using zap as a dependency.

Example: A critical vulnerability is discovered in a Go standard library package that zap utilizes for network operations. An attacker could exploit this vulnerability by crafting malicious log messages sent to a network sink configured with zap, potentially leading to remote code execution in the application.

Impact:

• Remote Code Execution (RCE).
• Denial of Service (DoS).
• Information Disclosure.

Risk Severity: Critical to High (depending on the specific vulnerability).

Mitigation Strategies:

• Regularly Update Dependencies: Keep zap and all its dependencies updated to the latest versions to patch known vulnerabilities. Use dependency management tools to facilitate updates.
• Dependency Scanning and Monitoring: Implement dependency scanning tools (e.g., govulncheck, Snyk, OWASP Dependency-Check) in your development and CI/CD pipelines to automatically detect and alert on vulnerabilities in zap's dependencies.
• Vulnerability Awareness: Stay informed about security advisories and vulnerability databases related to Go and the libraries used by zap.

Attack Surface: Configuration Management and Secrets Exposure

Description: Sensitive credentials, such as API keys or passwords required for certain zap sink configurations (e.g., cloud logging services), are exposed due to insecure configuration management practices. This is directly related to how zap configurations are handled.

Zap Contribution: zap configurations can include sensitive information like credentials for external logging services. If these configurations are not managed securely, using zap can indirectly lead to secrets exposure.

Example: API keys for a cloud-based logging service are hardcoded directly within the zap configuration code or stored in plain text configuration files that are committed to version control. If the code repository is compromised or accessible to unauthorized individuals, these API keys are exposed.

Impact:

• Exposure of sensitive credentials (API keys, passwords).
• Unauthorized access to logging services or other systems protected by the exposed credentials.
• Potential data breaches if compromised logging services contain sensitive information.

Risk Severity: Critical to High (depending on the sensitivity of the exposed secrets).

Mitigation Strategies:

• Secure Secrets Management: Utilize dedicated secrets management solutions (e.g., HashiCorp Vault, AWS Secrets Manager, environment variables) to store and manage sensitive credentials required for zap configurations. Avoid hardcoding secrets in code or configuration files.
• Configuration Security Best Practices: Follow secure configuration management practices. Store zap configuration files securely, restrict access, and avoid committing sensitive configurations to version control without proper encryption or secrets management.
• Principle of Least Privilege: Grant only the necessary permissions to access logging services and related infrastructure, minimizing the impact of compromised credentials.