browser-exploitation-v8

browser-exploitation-v8 is a skill for Claude Code, Codex from ShulkwiSEC/bb-huge. It costs 50 tokens per session (3,036 once invoked), scanned A, a copy of browser-exploitation-v8, MIT.

An exploitation playbook for vulnerabilities in V8, the JavaScript engine used by Chrome and Chromium browsers. It covers engine bugs such as JIT type confusion and memory corruption, along with browser sandbox escape concepts.

In plain words
What is it for?
Use it when researching or developing exploits for Chrome or Chromium renderer vulnerabilities, including type confusion, memory corruption, sandbox bypass, and remote code execution.
Why use it?
It provides a structured reference for complex browser exploitation work, where JavaScript engine internals and memory protections make bugs difficult to turn into code execution.

Skill for Claude CodeCodex

Written for no agent in particular: nothing here depends on one.

Good fit Use it when researching or developing exploits for Chrome or Chromium renderer vulnerabilities, including type confusion, memory corruption, sandbox bypass, and remote code execution.

Compare 6 skills from other repositories ↓
Install with agentmods
npx agentmods add skills/shulkwisec/bb-huge/browser-exploitation-v8
Install

Getting it into your agent

One page per mod, every tool's command on it. A separate URL per tool would split the same page into five that compete with each other.

Any agent
npx skills add ShulkwiSEC/bb-huge --skill browser-exploitation-v8
Clone the repo
git clone --depth 1 https://github.com/ShulkwiSEC/bb-huge

Made for: Claude Code, Codex.

Wrote this? Show the measurements

A badge with what this costs and how it scanned, read live from this page, so it follows the numbers instead of freezing them. Markdown for a README, HTML for a documentation site or a project page.

agentmods badge for browser-exploitation-v8

README.md
[![agentmods](https://agentmods.dev/badge/skills/shulkwisec/bb-huge/browser-exploitation-v8.svg)](https://agentmods.dev/skills/shulkwisec/bb-huge/browser-exploitation-v8)
Your own site
<a href="https://agentmods.dev/skills/shulkwisec/bb-huge/browser-exploitation-v8"><img src="https://agentmods.dev/badge/skills/shulkwisec/bb-huge/browser-exploitation-v8.svg" alt="Measured on agentmods" height="20"></a>
Per session 50 Skills are progressive disclosure: only the name and description are preloaded; the body loads when the skill is used.
When invoked 3,036 The whole file, excluding the scripts and references it only reads on demand.
Security scan A 0 findings. A grade says what 26 rules found in the file — not that it is safe.
Origin 100% copy Near-identical to another mod in the catalogue.
Token cost

What it costs to keep this loaded

Counted locally with the o200k_base tokenizer, which is exact for GPT models; Claude uses its own tokenizer and its counts differ. Treat this as one consistent yardstick across the catalogue rather than a bill. Prices are per million input tokens.

ModelPer sessionOnce invoked
Fable 5.1 $0.00050 $0.03036
Opus 5 $0.00025 $0.01518
Sonnet 5 $0.00010 $0.00607
Haiku 4.5 $0.00005 $0.00304

Measured 4d ago against content hash 47a589e8a3dd, method: parsed. Prices are Anthropic first-party input rates as of 2026-09-07, from the pricing page.

Security

Grade A, and why

browser-exploitation-v8 scanned grade A with 0 findings against 26 rules in 11 categories — prompt injection, anti-refusal, data exfiltration, privilege escalation, supply chain, agent snooping, system-prompt leakage, SSRF and excessive agency — measured 4d ago.

A static scan of the body, not an audit. Every finding is printed with the line that produced it so you can judge whether it matters here. A mod is markdown that instructs an agent; that is exactly why what it instructs is worth reading.

Nothing flagged

None of the 26 patterns this scan looks for appear in this file: no shell pipes, no recursive deletes, no credential paths, no hidden text, no instruction-override or anti-refusal phrasing, no agent-config snooping. That is not a guarantee, it is the absence of the things that are checkable.

Origin

This is a copy

100% identical to browser-exploitation-v8 — 0 lines differ, which has more behind it and is treated as the original. This page carries a canonical link to it rather than competing with it.

skills/curated/browser-exploitation-v8/SKILL.md · 335 lines

How it starts

The opening of the file, as written. The whole thing — 335 lines — stays where its author put it; the contents beside it link to each section on GitHub.

SKILL: Browser / V8 Exploitation — Expert Attack Playbook

AI LOAD INSTRUCTION: Expert V8/Chrome exploitation techniques. Covers V8 compilation pipeline, JIT type confusion, addrof/fakeobj primitives, ArrayBuffer corruption, WASM RWX pages, V8 sandbox (pointer compression), and Chrome sandbox escape overview. Distilled from ctf-wiki browser sections, Project Zero research, and CTF competition patterns. Base models often confuse V8 object representation details and miss the pointer compression barrier.

Advanced Reference

Load V8_EXPLOITATION_PATTERNS.md when you need:

  • Detailed exploitation patterns and code templates
  • Heap layout manipulation and GC interaction
  • V8 sandbox bypass techniques
  • Object map confusion patterns

1. V8 ARCHITECTURE

Compilation Pipeline

JavaScript Source
    ↓ Parser
  AST (Abstract Syntax Tree)
    ↓ Ignition
  Bytecode (interpreted, profiling)
    ↓ Sparkplug (non-optimizing baseline, V8 ≥ 9.1)
  Baseline code (fast startup)
    ↓ Maglev (mid-tier, V8 ≥ 10.2)
  Mid-optimized code
    ↓ TurboFan (optimizing JIT)
  Optimized machine code (with speculative optimizations)
    ↓ Deoptimization (if speculation fails)
  Back to Ignition bytecode

Key V8 Concepts

Concept Description
Tagged pointers SMI (Small Integer): value << 1, HeapObject: ptr | 1
Pointer compression V8 ≥ 8.0: objects addressed via 32-bit offset from cage base (4GB sandbox)
Maps (Hidden Classes) Define object shape: property names, types, offsets
Elements kinds Internal array type: PACKED_SMI_ELEMENTS, PACKED_DOUBLE_ELEMENTS, PACKED_ELEMENTS, etc.
Write barrier GC bookkeeping when heap pointers are written
Garbage collection Orinoco GC: minor (Scavenge) and major (Mark-Compact)

Read the full file on GitHub · 335 lines

Files

What ships with it

1 file beside SKILL.md in the same directory: the scripts, references and assets a skill reads on demand. Not counted in the per-session cost; read them before you install if any of them is executable.

Changes

What this file has done since we first saw it

Hashed on every crawl. A supply-chain change to an agent config is a question of when, not whether, so the history is kept rather than the latest state alone.

  1. 4d ago First seen · 335 lines · 50 tokens per session scan A 47a589e8a3dd

Subscribe to this mod's changes

browser-exploitation-v8 is a skill published in the GitHub repository ShulkwiSEC/bb-huge (22 stars, last pushed 1mo ago), licensed MIT. It adds 50 tokens to every session and 3,036 once invoked, about $0.0003 per session on Opus 5. A static security scan graded it A with 0 findings. It is 100% identical to browser-exploitation-v8, differing in 0 lines, and is treated as a copy.

Related

Other skills, from other repositories