# MAL-2026-10723: Malicious code in @yeaft/webchat-agent (npm)


- **Type:** Malicious package
- **Package:** `@yeaft/webchat-agent` (npm)
- **Published:** 16 Jul 2026

## What is MAL-2026-10723?

MAL-2026-10723 is a malicious package in @yeaft/webchat-agent, published on 16 Jul 2026. 

### Official description

The package installs itself as a user-level service (systemd on Linux via service/linux.js, with launchd/PM2 siblings) and, at agent startup, opens a WebSocket to a configured serverUrl (default ws://localhost:3456, overridable via SERVER_URL/config). The WebSocket message router in connection/message-router.js dispatches server-sent frames: `terminal_create` spawns the user's login shell via node-pty (terminal.js: `pty.spawn(shell,...)`) in the agent's workDir, and `terminal_input` writes the server's `msg.data` bytes directly into that PTY, giving whoever controls the server (or an attacker holding AGENT_SECRET / positioned to MITM the WebSocket) an interactive shell as the installing user. An `upgrade_agent` message handled by connection/upgrade.js runs `npm install @yeaft/webchat-agent@latest --registry=https://pkg.yeaft.com/` and spawns a detached script that stops the service, installs the new version, and restarts it, so the remote party can also swap the agent's own code on demand from a publisher-controlled registry. On every startup, index.js additionally git-clones https://github.com/yeaft/yeaft-skills.git from the mutable `main` branch into ~/.claude/plugins/marketplaces/yeaft-skills-dev, chmod 0755 the hook scripts, and writes the plugin as enabled into ~/.claude/settings.json, giving whoever controls that repo the ability to land executable Claude plugin hooks on the next agent boot. The service/linux.js unit also prepends ~/.local/bin and ~/.npm-global/bin to PATH in the service environment. The remote-shell and self-upgrade paths are the package's advertised remote-agent purpose, but by threat-model definition a network-source-to-spawned-PTY dataflow on the installer's host is a backdoor, and the blast radius is full-host code execution as the installing user.

## What should I do about MAL-2026-10723?

Remove the package from your dependencies and lockfiles, then rotate any secrets on machines where it was installed.

## Fix prompt for AI coding agents

```text
MAL-2026-10723 is a malicious package: @yeaft/webchat-agent (npm). Every version was published to cause harm.

Task:
1. Search this repository's dependency manifests and lockfiles for the package, including transitive dependencies.
2. If it is present, remove it, regenerate the lockfile with the project's package manager, and replace whatever it was used for.
3. List any CI runners, developer machines or containers that installed it, so their secrets can be rotated.
4. If the package is not used anywhere, say so and change nothing.

Reference: https://insights.sbomify.com/MAL-2026-10723/ (Markdown: https://insights.sbomify.com/MAL-2026-10723/index.md)
```

## Sources

- OSV: https://osv.dev/vulnerability/MAL-2026-10723

---
From sbomify Insights: https://insights.sbomify.com/MAL-2026-10723/
Summaries are generated and may contain mistakes; the official description above is the record.