Threat Model Analysis for gabime/spdlog

Threat: Configuration Manipulation (Spoofing)

Threat: Configuration Manipulation (Spoofing)
- Description: An attacker modifies the spdlog configuration (e.g., via a vulnerable configuration file, environment variables, or command-line arguments) to redirect log output to a file or network location they control, disable logging entirely, or change log levels to suppress critical events. This directly targets spdlog's configuration mechanisms.
- Impact: Loss of log integrity, potential for attackers to cover their tracks, inability to audit security events, potential information disclosure if logs are redirected to an attacker-controlled location.
- Affected spdlog Component: Configuration loading mechanisms (e.g., spdlog::from_file, environment variable parsing, command-line argument processing), sink creation (based on the manipulated configuration).
- Risk Severity: High
- Mitigation Strategies:
  - Strictly validate and sanitize all external inputs used to configure spdlog. Use a whitelist approach.
  - Protect configuration files with appropriate file system permissions (read-only for most users).
  - Use a secure configuration management system.
  - Log changes to the spdlog configuration itself to a separate, secure log.

Threat: Log File Tampering
- Description: An attacker with write access to the log files modifies or deletes log entries to remove evidence of malicious activity or inject false information. This directly affects the output produced by spdlog's file sinks.
- Impact: Loss of log integrity, inability to accurately investigate security incidents, potential for misleading investigations.
- Affected spdlog Component: File sinks (e.g., spdlog::sinks::basic_file_sink, spdlog::sinks::rotating_file_sink), potentially custom sinks if they don't implement proper access controls.
- Risk Severity: High
- Mitigation Strategies:
  - Restrict write access to log files to the application user only (principle of least privilege).
  - Implement File Integrity Monitoring (FIM).
  - Use rotating file sinks with limited file count and size.
  - Log to a remote, secure logging server (SIEM).
  - Implement cryptographic signing of log entries (custom sink).

Threat: Format String Vulnerability within Logging
- Description: An attacker provides malicious input that is used as part of a format string within a spdlog logging call. If the format string itself is sourced from untrusted input, this could lead to a denial-of-service or potentially arbitrary code execution. This is a vulnerability within spdlog's formatting logic.
- Impact: Denial of service, potential for arbitrary code execution (though less likely with modern compilers and libraries).
- Affected spdlog Component: Format string processing within spdlog::logger::log (and related functions), custom formatters if they handle user input unsafely.
- Risk Severity: High (if format strings are sourced from untrusted input)
- Mitigation Strategies:
  - Never source format strings from untrusted input. Hardcode format strings.
  - If configurable format strings are essential, use a very strict whitelist of allowed format specifiers.
  - Keep spdlog updated.

Threat: Sensitive Data Exposure in Logs
- Description: Although primarily a developer error, spdlog is the mechanism by which sensitive data (passwords, API keys, PII) is exposed if the application inadvertently logs it. The threat is the use of spdlog to write this sensitive data.
- Impact: Information disclosure, potential for credential theft, privacy violations.
- Affected spdlog Component: All sinks (since they all write the log data), potentially custom formatters if they don't handle sensitive data properly.
- Risk Severity: High
- Mitigation Strategies:
  - Code review to prevent logging of sensitive data.
  - Implement data masking/redaction (custom formatter or sink).
  - Use appropriate log levels (avoid sensitive data at DEBUG/TRACE).
  - Sanitize user input before logging.