| name | analyzing-taint-flow |
| description | Tracks untrusted input propagation from sources to sinks in binary code to identify injection vulnerabilities. Use when analyzing data flow, tracing user input to dangerous functions, or detecting command/SQL injection. |
Taint Analysis
Detection Workflow
- Identify sources: Find recv, read, getenv, fgets, scanf, argv (input functions)
- Identify sinks: Find system, popen, strcpy, sprintf, execve, malloc (dangerous functions)
- Find taint paths: Use
xrefs_toto trace from sources to sinks - Analyze sanitization: Check for input validation, length checks, character filtering, encoding/escaping
- Assess risk: Determine reachability, check if attacker controls critical parts, evaluate exploitability
Key Patterns
- Direct command injection: recv() -> buffer -> sprintf(cmd, "echo %s", buffer) -> system(cmd)
- Path traversal: fgets() -> filename -> fopen(filename, "r")
- Buffer overflow via tainted size: recv() -> size_buffer -> atoi(size_buffer) -> malloc(size)
Output Format
Report taint paths with: source (function, address, context), sink (function, address, context), path (list of functions), sanitizers_found, is_vulnerable, confidence, vulnerability_type.
Severity Guidelines
- CRITICAL: Direct injection with no sanitization (command injection, SQL injection)
- HIGH: Path traversal, buffer overflow via tainted size
- MEDIUM: Potential injection with partial sanitization
- LOW: Tainted data with limited impact
See Also
patterns.md- Detailed detection patterns and exploitation scenariosexamples.md- Example analysis cases and code samplesreferences.md- CWE references and mitigation strategies