detecting-integer-overflow

name	detecting-integer-overflow
description	Detects integer overflow and underflow vulnerabilities in arithmetic operations used for buffer sizing or allocation. Use when analyzing calculations, size computations, or investigating integer wraparound issues.

Integer Overflow Detection

Detection Workflow

1. Identify arithmetic operations: Find addition, multiplication, subtraction, bit shifts on user-controlled values
2. Check for overflow protection: Look for overflow checks before arithmetic, safe arithmetic functions, type conversions
3. Trace to critical uses: Follow results to memory allocation sizes, buffer copy lengths, loop bounds, array indices
4. Assess impact: Can overflow cause buffer overflow? Bypass security checks? Cause logic errors?

Key Patterns

• Addition/multiplication without overflow checks
• Subtraction that could underflow
• Integer overflow affecting malloc size
• Loop counter overflow

Output Format

Report with: id, type (addition/multiplication/underflow), severity, confidence, location, operation, operands, result used for, overflow check status, exploitability, impact, mitigation.

Severity Guidelines

• HIGH: Overflow affects memory allocation size
• MEDIUM: Overflow affects loop bounds or array indices
• LOW: Overflow with limited security impact

See Also

• patterns.md - Detailed detection patterns and exploitation scenarios
• examples.md - Example analysis cases and code samples
• references.md - CWE references and mitigation strategies