cwe-369-divide-by-zero

name	cwe-369-divide-by-zero
description	Use this skill when you need to remediate CWE-369 (Divide By Zero) vulnerabilities in Java code. Triggers on SAST findings, security reviews, or when fixing divide by zero issues.
version	1.0.0
license	MIT
tags	["security","java","cwe-369","remediation","sast"]

CWE-369 Divide By Zero

Description

Divide By Zero

Reference: https://cwe.mitre.org/data/definitions/369.html

OWASP Category: A03:2021 – Injection

---

Vulnerable Pattern

❌ Example 1: Vulnerable Pattern

// VULNERABLE: No check for zero divisor
int result = total / count;

Why it's vulnerable: This pattern is vulnerable to Divide By Zero

---

Deterministic Fix

✅ Secure Implementation: Secure Implementation

// SECURE: Check divisor before division
if (count == 0) {
    throw new IllegalArgumentException("Division by zero");
    // Or return default value
    // return 0;
}
int result = total / count;

Why it's secure: Implements proper protection against Divide By Zero

---

Detection Pattern

Look for these patterns in your codebase:

# Find division operations
grep -rn "/[^/*]\\|% " --include="*.java" | grep -v "//"

---

Remediation Steps

1. Always check divisor is not zero before division

2. Handle zero case explicitly with default value or exception

---

Key Imports

---

Verification

After remediation:

• Run SAST scanner to confirm vulnerability is resolved

• Review all instances of the vulnerable pattern

• Add unit tests that verify the secure implementation

• Check for similar patterns in related code

---

Trigger Examples

Fix CWE-369 vulnerability
Resolve Divide By Zero issue
Secure this Java code against divide by zero
SAST reports CWE-369

---

Common Vulnerable Locations

Layer	Files	Patterns

| Controller | *Controller.java | User input handling |

| Service | *Service.java | Business logic |

| Repository | *Repository.java | Data access |

---

References

• CWE-369: Divide By Zero

---

Source: Generated by Java CWE Security Skills Generator Last Updated: 2026-03-07