vuln-screenshot

AI reproduced the vulnerability. Why are you still taking screenshots by hand?

简体中文 · MCP guide · Evidence format · Security model

AI-assisted vulnerability research often stops one step before the report is ready:

• The AI runs a PoC but returns only a text summary, making the request, response, and command output difficult to review at a glance.

• The AI drafts the vulnerability report without reproduction screenshots, leaving a human to rerun commands, paste raw requests, and capture the evidence manually.

• Manually produced screenshots are inconsistent, and the visual result is easily separated from the raw evidence behind it.

Finish the last mile with vuln-screenshot

vuln-screenshot lets an AI call a local CLI or Model Context Protocol server to:

• send a real raw HTTP/1.1 request and generate a Burp Suite-style request/response screenshot;

• execute a real command in a pseudo-terminal and generate a screenshot containing only the command and its response;

• preserve the original HTTP bytes, terminal stream, normalized text, and a machine-readable manifest;

• produce consistent, report-ready images without asking a human to repeat the reproduction process.

The AI reproduces the vulnerability. vuln-screenshot turns the result into visual, consistent, and reviewable evidence.

Related MCP server: Screen MCP

See it in action

The following images were generated from an authorized local reproduction of GitLab CVE-2026-85706. The target uses a loopback address and the displayed values are demonstration data.

Raw HTTP request and response

Command and terminal response

Why vuln-screenshot?

• Real inputs, not reconstructed snippets. Raw request bytes, duplicate headers, bodies, CRLF boundaries, ANSI output, and non-zero exits are preserved.

• Evidence before decoration. Screenshots are presentation artifacts; the accompanying raw files remain the source evidence.

• Built for reports. HTTP output uses a compact request/response workbench and terminal output contains only the command and its response.

• CLI and MCP. Use it from a shell or expose the same capture operations to an MCP-compatible host.

• Explicit limits. Truncation, timeouts, render failures, and transport metadata are recorded rather than hidden.

Requirements

• Node.js 20 or newer

• macOS or Linux

• Chromium installed by Playwright, or a local Google Chrome/Chromium installation

Install

From the repository:

git clone https://github.com/jweny/vuln-screenshot.git
cd vuln-screenshot
npm install
npm run install-browser
npm run build

After the package is published to npm, it can also be installed globally:

npm install --global vuln-screenshot

On Unix, the postinstall step and command capture both ensure that node-pty's prebuilt helper has the executable bit required to start a PTY. The runtime check also covers package managers that disable dependency install scripts.

Quick start

Capture a raw HTTP/1.1 request:

printf 'GET / HTTP/1.1\r\nHost: example.com\r\nConnection: close\r\n\r\n' | \
  vuln-screenshot http --target https://example.com --request -

--target selects the TCP/TLS destination only. Request bytes are sent unchanged. Use --request - to read from stdin and --insecure only for an intentionally untrusted or self-signed TLS target.

A reusable request file is available at examples/requests/example.raw.

Capture a command:

vuln-screenshot command --cwd /tmp -- \
  'printf "\033[32mevidence captured\033[0m\n"; uname -a'

Commands run as $SHELL -lc with the current user's permissions. PTY output merges stdout and stderr, matching a real terminal. Set VULN_SCREENSHOT_OUTPUT_DIR to change the default ./artifacts output root.

When running from a source checkout, replace vuln-screenshot with node dist/cli.js.

Evidence bundle

HTTP captures produce:

artifacts/<UTC timestamp>-<UUID>/
├── manifest.json
├── request.raw
├── response.raw
└── screenshots/
    └── 001.png ...

Command captures use command.txt, terminal.raw, and terminal.txt instead. Directories use mode 0700 and files use 0600 where the platform supports POSIX permissions.

See Evidence format for the manifest contract and Architecture for the capture pipeline.

MCP server

Start the stdio server:

vuln-screenshot mcp

It exposes:

• capture_http_evidence — send one raw HTTP/1.1 request and preserve the response.

• capture_command_evidence — execute one non-interactive command in a host PTY.

See MCP integration for configuration and input schemas.

Limits and security

• HTTP/1.1 only; no redirect, retry, cookie jar, proxy, or request normalization.

• Response and PTY capture limit: 10 MiB.

• Screenshot limit: 100 pages.

• Default timeouts: 30 seconds for HTTP and 60 seconds for commands; maximum 5 minutes.

• Credentials, cookies, commands, and output are preserved without redaction.

• Manifests currently do not contain hashes or digital signatures and are not tamper-proof.

• The command tool executes with the current user's full host permissions.

Use the tool only against systems you own or are explicitly authorized to test. Read the threat model before integrating it into an automated agent.

Development

npm ci
npm run install-browser
npm run check
npm test
npm run build
npm pack --dry-run

Tests use local TCP fixtures and do not require an external target. See CONTRIBUTING.md for the contribution workflow.

License

Licensed under the Apache License 2.0.