name: injection-hunter description: Hunt for injection vulnerabilities including SQL injection, command injection, XSS, SSTI, path traversal, LDAP injection, and other input validation flaws. Use when auditing code that processes user input.
Injection Vulnerability Hunter
Purpose
Identify injection vulnerabilities by tracing user input from sources to dangerous sinks. Covers SQL injection, OS command injection, XSS, SSTI, path traversal, LDAP injection, and XML injection.
Focus Areas
- SQL Injection: String concatenation in queries, ORM bypass
- Command Injection: Unsanitized input in system(), exec(), shell commands
- XSS (Cross-Site Scripting): Reflected, stored, DOM-based
- SSTI (Server-Side Template Injection): User input in templates
- Path Traversal: User input in file paths without sanitization
- LDAP/XML/Header Injection: Protocol-specific injection attacks
Taint Analysis Approach
1. Identify Sources (User Input)
- request.params, request.body, request.query
- HTTP headers (Host, User-Agent, Referer, X-Forwarded-For)
- File uploads (filename, content)
- Database values (stored attacks)
- Environment variables (in some contexts)
- WebSocket messages
2. Track Flow Through Code
Follow data transformations:
- Variable assignments
- Function parameters
- Return values
- Object properties
3. Identify Dangerous Sinks
SQL: db.query(), db.execute(), raw SQL strings
Command: system(), exec(), popen(), spawn(), backticks
XSS: innerHTML, document.write(), dangerouslySetInnerHTML
SSTI: render(), template(), eval() with user data
Path: open(), readFile(), fs.*, path.join() with user input
LDAP: ldap.search() with user-controlled filter
Output Format
findings:
- title: "SQL Injection in search endpoint"
severity: critical
attack_scenario: "Attacker injects SQL via 'query' parameter to extract database"
preconditions: "None - public endpoint"
reachability: public
impact: "Full database compromise, data exfiltration"
confidence: high
cwe_id: "CWE-89"
affected_assets:
- "/api/search?query="
- "src/handlers/search.rs:45"
taint_path: "request.query['query'] -> format!() -> db.execute()"
Key Patterns by Injection Type
SQL Injection
// VULNERABLE - string concatenation
let query = format!("SELECT * FROM users WHERE name = '{}'", user_input);
db.execute(&query)?;
// SECURE - parameterized query
db.execute("SELECT * FROM users WHERE name = ?", &[user_input])?;
Command Injection
# VULNERABLE
os.system(f"convert {filename} output.png") # filename = "; rm -rf /"
# SECURE
subprocess.run(["convert", filename, "output.png"]) # Array form
XSS (Cross-Site Scripting)
// VULNERABLE - direct HTML insertion
element.innerHTML = userInput;
// SECURE - text content only
element.textContent = userInput;
Path Traversal
// VULNERABLE
path := filepath.Join("/uploads", userInput) // userInput = "../../../etc/passwd"
// SECURE
path := filepath.Join("/uploads", filepath.Base(userInput)) // Strip directory components
SSTI (Server-Side Template Injection)
# VULNERABLE
template = f"Hello {user_input}" # user_input = "{{7*7}}" or worse
render_template_string(template)
# SECURE
render_template("hello.html", name=user_input) # Template is static
Severity Guidelines
| Type | Impact | Severity |
|---|---|---|
| SQL Injection | DB access | Critical |
| Command Injection | RCE | Critical |
| Stored XSS | Session hijack | High |
| Reflected XSS | Phishing | Medium |
| SSTI with RCE | RCE | Critical |
| Path Traversal (read) | Info disclosure | High |
| Path Traversal (write) | Code execution | Critical |
Common Bypass Techniques to Consider
SQL: UNION, nested queries, time-based blind, error-based
CMD: &&, ||, ;, |, $(), backticks, newlines
XSS: Event handlers, data: URLs, SVG, encoding bypass
Path: ../, ..\\, URL encoding, double encoding, null bytes
KYCo Integration
Register injection findings and import scanner results:
1. Check Active Project
kyco project list
2. Register Finding
kyco finding create \
--title "SQL Injection in search endpoint" \
--project PROJECT_ID \
--severity critical \
--cwe CWE-89 \
--attack-scenario "Attacker injects SQL via 'query' parameter to extract database" \
--impact "Full database compromise, data exfiltration" \
--assets "/api/search,src/handlers/search.rs:45"
3. Import Scanner Results
# Import SARIF output
kyco finding import scanner-results.sarif --project PROJECT_ID
# Import Semgrep JSON
kyco finding import semgrep-results.json --project PROJECT_ID -f semgrep
Common CWE IDs for Injection
- CWE-89: SQL Injection
- CWE-78: OS Command Injection
- CWE-79: Cross-site Scripting (XSS)
- CWE-22: Path Traversal
- CWE-94: Code Injection
- CWE-1336: SSTI