type-juggling

Detect PHP type juggling and weak comparison vulnerabilities in legacy code.

Updated Jun 11, 2026

Search Tags:#security #vulnerability detection #PHP #type juggling #weak comparison

Ready to run

npx skills add https://github.com/utsavthakur/agenticskills --skill type-juggling-utsavthakur

💬 Prompt for ChatGPT / Claude Chat▼

Please help me install this Agent Skill.
Skill: type-juggling
Source: https://github.com/utsavthakur/agenticskills/tree/main/type-juggling
Command: npx skills add https://github.com/utsavthakur/agenticskills --skill type-juggling-utsavthakur

SYSTEM DOCUMENTATION & REQUIREMENTS

💡 This Skill includes scripts (resource) and references (resource) components.

What problem does it solve?

This Skill identifies PHP type juggling and weak comparison vulnerabilities, such as those found in authentication, HMAC/signature checks, or token validation.

Core Features & Use Cases

Type Juggling Detection: Identifies instances where '==' is used instead of '===', leading to security issues.
Magic Hash Detection: Detects cases where MD5 or SHA-1 hashes are compared as strings, which can be exploited.
HMAC Bypass Detection: Identifies logic that uses loose comparison against a constant like '0' or an empty string.
Use Case: If you suspect that a PHP application may be vulnerable to type juggling or weak comparison, use this Skill to test for such vulnerabilities.

Quick Start

Use the type-juggling skill to test the authentication system for PHP type juggling and weak comparison vulnerabilities.

Frequently Asked Questions about type-juggling

High-intent search queries and answers about installing and using this skill.

FAQPage Schema

How do I detect PHP type juggling and weak comparison vulnerabilities in legacy code?▼

PHP type juggling occurs when loose equality operators like '==' cause automatic type coercion during comparisons. This becomes a security vulnerability in authentication or token validation when numeric strings or magic hashes bypass checks against constants like '0'.

How does weak comparison lead to HMAC bypass and magic hash vulnerabilities in PHP?▼

Weak comparison leads to HMAC bypass when logic compares values against constants like '0' or an empty string using '==' instead of '==='. Magic hash vulnerabilities occur when MD5 or SHA-1 hashes are compared as strings, allowing exploitation through type coercion.

Do I need to specify the PHP version and code paths to check for loose equality vulnerabilities?▼

You must provide the specific PHP version and knowledge of the code paths for effective type juggling and weak comparison vulnerability analysis. This context is required to accurately detect loose equality issues in legacy PHP applications.

What is the best way to test authentication systems for PHP type juggling vulnerabilities?▼

The best way to test authentication systems for PHP type juggling vulnerabilities is to scan for loose equality usage, magic hash comparisons, and HMAC signature checks without strict types. Focus analysis specifically on authentication logic and token validation paths.

When should I check my PHP application for weak comparison and type coercion security issues?▼

You should check for weak comparison and type coercion security issues when auditing legacy PHP code, particularly if the application handles authentication, HMAC signature checks, or token validation and may use loose equality instead of strict types.