config-file-parsing-bugs

Detect INI parser vulnerabilities by targeting fixed-size fgets() buffer truncation and last-key-wins duplicate overwrites to inject malicious entries that bypass access controls. This skill identifies these flaws in C-based parsers like inih and PAM.

Line truncation in C-based config parsers occurs when fixed-size fgets() buffers silently cut off long input lines. This allows attackers to inject malicious config entries, causing critical vulnerabilities if parsed values dictate authentication or service configuration.

Duplicate key overwrite attacks exploit last-key-wins behavior in YAML and TOML parsers to silently override legitimate configuration values. This skill detects these parsing quirks to help red teamers bypass application configuration controls.

It detects environment variable interpolation flaws, encoding differentials, and whitespace handling issues in config parsing logic. These parser quirks lead to unexpected interpretation of values and severe security misconfigurations in target applications.

It is designed for penetration testing applications that process user-influenced config files for authentication, access control, or service configuration. It identifies parsing logic flaws across INI, YAML, TOML, and C-based parsers.

Limitations include relying on the target application using vulnerable parser implementations like inih or PAM with fixed-size buffers. Testing is constrained to detecting specific encoding differentials, line truncation, and duplicate key overwrite behaviors in config parsing logic.