Prototype Pollution Attack

Prototype Pollution Attack is a Quality skill for Claude Code, published by CyberStrikeus in CyberStrike.

1.7K stars269 forkson CyberStrikeus/CyberStrikeAdded 2026/08/12+4% in starsRepository updated 2026/08/12

aiai-agentai-securitybug-bountycybersecuritydevsecopsethical-hackinghackinghacking-toolllmmcpmcp-servermitre-attackoffensive-securityowasppenetration-testingpentestred-teamsecuritysecurity-tools

Install in seconds

Install Prototype Pollution Attack

Copy Prototype Pollution Attack into your Claude Code skills folder. Run the command in your terminal, or review the source on GitHub before installing.

terminal

npx degit https://github.com/CyberStrikeus/CyberStrike/tree/main/.cyberstrike/skill/attack-prototype-pollution ~/.claude/skills/attack-prototype-pollution

Requires Node.js. Downloads this skill only — not the rest of the repository — into your Claude Code skills folder.

Without Node.js

git clone https://github.com/CyberStrikeus/CyberStrike.git

Clones the whole repository, then copy the skill’s own directory into your skills folder yourself.

In this catalog

Source file: .cyberstrike/skill/attack-prototype-pollution/SKILL.md in CyberStrikeus/CyberStrike
Installs to: ~/.claude/skills/attack-prototype-pollution
Collection: One of 51 skills cataloged from this repository
Category: Quality — 1354 skills

What Prototype Pollution Attack does

Prototype Pollution Attack outlines how to test JavaScript apps for __proto__ and constructor.prototype pollution. Use it when checking merge or parse endpoints for client-side XSS, privilege escalation, or server-side gadget chains.

Prototype Pollution Attack is cataloged under Quality on DirSkills. Prototype Pollution Attack comes from a repository tagged ai, ai-agent, ai-security, bug-bounty and cybersecurity.

Documentation

README

Excerpt

Prototype Pollution

Objective

Exploit JavaScript prototype pollution to modify Object.prototype, leading to XSS, privilege escalation, or RCE via gadget chains.

Testing Methodology

Phase 1: Client-Side Detection

URL-based pollution:

https://TARGET/?__proto__[polluted]=1
https://TARGET/?__proto__.polluted=1
https://TARGET/?constructor[prototype][polluted]=1
https://TARGET/#__proto__[polluted]=1

Verify in browser console:

console.log(({}).polluted) // Should print "1" if vulnerable

Phase 2: JSON Body Pollution

This is the opening of the README. Read the full README on GitHub.

Frequently asked about Prototype Pollution Attack

What else does CyberStrikeus publish alongside Prototype Pollution Attack?
Prototype Pollution Attack is one of 51 skills that DirSkills catalogs from CyberStrikeus/CyberStrike, the repository it ships in. Its siblings there include AMI Age Compliance, AMI Encryption Check and AMI Naming Convention Compliance. Each one is a separate skill with its own page in this directory, installs the same way Prototype Pollution Attack does, and is maintained by CyberStrikeus in that same repository. The rest of the collection is listed on the CyberStrikeus/CyberStrike page.
How does Prototype Pollution Attack compare to other Quality skills?
Prototype Pollution Attack ranks #605 by stars among the 1354 Quality skills in this catalog. The most-starred ones next to it are Benchmark, Benchmark Optimization Loop and API Design Patterns. DirSkills ranks by the star count of the repository each skill ships in, so that order reflects how popular those repositories are rather than any review of Prototype Pollution Attack against them. Open each page to compare what they document and how they install.