Individual skill
prototype-pollution
Hunt JavaScript prototype pollution (CWE-1321) — the 2023-2026 meta-vulnerability that chains into RCE, auth bypass, and SSRF on most Node.js stacks.
packages/decepticon/decepticon/skills/standard/analyst/prototype-pollution/SKILL.md
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# Prototype Pollution Playbook
Prototype pollution is the JavaScript equivalent of a universal gadget:
plant a property on `Object.prototype` and it appears on every object in
the runtime. Worthless in isolation, deadly in chain (`__proto__.isAdmin
= true` → auth bypass; `__proto__.shell = "/bin/bash"` → RCE via `spawn`).
## 1. Sinks — the libraries that still introduce sinks
Keep a running list per engagement. These continue to ship sinks in 2026:
- **Deep-merge:** `lodash.merge`, `deepmerge` (pre-fix), `merge-deep`, `deepExtend`, `hoek.merge`, `mixme`
- **Deep-clone:** `lodash.defaultsDeep`, `lodash.zipObjectDeep`, `set-value` (pre-3.0.3)
- **URL-to-obj:** `qs`, `express-fileupload`, `jquery.extend(true, ...)`