# `@metamask/permission-controller`

Mediates access to JSON-RPC methods, used to interact with pieces of the MetaMask stack, via middleware for `@metamask/json-rpc-engine`.

## Installation

`yarn add @metamask/permission-controller`

or

`npm install @metamask/permission-controller`

## Understanding

Please read the [Architecture][./architecture.md] document for more on how PermissionController works and how to use it.

## Contributing

This package is part of a monorepo. Instructions for contributing can be found in the [monorepo README](https://github.com/MetaMask/core#readme).


Mediates access to JSON-RPC methods, used to interact with pieces of the MetaMask stack, via middleware for json-rpc-engine

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@metamask/permission-controller

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permission-controller

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Ambiguous License Classifier

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Bad text encoding

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Bad semver

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Bad dependency semver

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Bidirectional unicode control characters

This package has multiple bin scripts with the same name. This can cause non-deterministic behavior when installing or could be a sign of a supply chain attack.

What is bin script confusion?

Bin script confusion

This Chrome extension includes content scripts that execute JavaScript on specified websites.

What are Chrome extension content scripts?

Chrome: Content Script

This Chrome extension requests host permissions to access specific websites or domains.

What are Chrome extension host permissions?

Chrome: Host Permission

This Chrome extension requests permissions to access browser APIs, user data, or system features.

What are Chrome extension permissions?

Chrome: Permission

This Chrome extension requests wildcard host permissions that grant broad access to websites.

What are Chrome extension wildcard host permissions?

Chrome: Wildcard Host Permission

Semantic versions published out of chronological order.

What is a chronological version anomaly?

Chronological version anomaly

Project maintainer's SSH key has been compromised.

What is a compromised SSH key?

Compromised SSH key

What do I need to know about license files?

Copyleft License

Contains a Critical Common Vulnerability and Exposure (CVE).

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Title

Critical CVE

Contains a high severity Common Vulnerability and Exposure (CVE).

What is a CVE?

High CVE

Uses debug, reflection and dynamic code execution features.

What is debug access?

Debug access

The maintainer of the package marked it as deprecated. This could indicate that a single version should not be used, or that the package is no longer maintained and any new vulnerabilities will not be fixed.

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Deprecated

Contains a known deprecated SPDX license exception.

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Deprecated SPDX exception

License is deprecated which may have legal implications regarding the package's use.

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Deprecated license

Package name is similar to other popular packages and may not be the package you want.

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Possible typosquat attack

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Dynamic require

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Empty package

Package accesses environment variables, which may be a sign of credential stuffing or data theft.

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Environment variable access

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File dependency

Accesses the file system, and could potentially read sensitive data.

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Filesystem access

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Wildcard dependency

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GitHub Actions: Input argument flows to dangerous sink

A GitHub context variable (such as issue title, PR description, or comment body) is being exported as an environment variable. These context values are user-controlled and could be exploited by subsequent workflow steps.

GitHub Actions: GitHub context variable exported as environment variable

A GitHub context variable (such as issue title, PR description, or comment body) is being passed back as an output. These context values are user-controlled and could be exploited by consuming workflows.

GitHub Actions: GitHub context variable passed back as output

A GitHub context variable (such as issue title, PR description, or comment body) flows into a dangerous sink (such as shell command execution). This is a critical security issue that could allow command injection or code execution attacks.

GitHub Actions: GitHub context variable flows to dangerous sink

An environment variable flows into a dangerous sink (such as shell command execution). If this environment variable comes from an untrusted source, it could be exploited to inject commands.

GitHub Actions: Environment variable flows to dangerous sink

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Git dependency

Contains a dependency which resolves to a GitHub URL. Dependencies fetched from GitHub specifiers are not immutable can be used to inject untrusted code or reduce the likelihood of a reproducible install.

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GitHub dependency

AI has identified unusual behaviors that may pose a security risk.

What is an AI-detected potential code anomaly?

AI-detected potential code anomaly

AI has identified this package as a potential typosquat of a more popular package. This suggests that the package may be intentionally mimicking another package's name, description, or other metadata.

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AI-detected possible typosquat

AI has identified this package as malware. This is a strong signal that the package may be malicious.

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AI-detected potential malware

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AI-detected potential security risk

Contains native code (e.g., compiled binaries or shared libraries). Including native code can obscure malicious behavior.

Why is native code a concern?

Native code

Contains high entropy strings. This could be a sign of encrypted data, leaked secrets or obfuscated code.

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High entropy strings

Contains unicode homoglyphs which can be used in supply chain confusion attacks.

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Unicode homoglyphs

Contains a dependency which resolves to a remote HTTP URL which could be used to inject untrusted code and reduce overall package reliability.

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HTTP dependency

Install scripts are run when the package is installed or built. Malicious packages often use scripts that run automatically to execute payloads or fetch additional code.

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Install scripts

Package has an invalid manifest file and can cause installation problems if you try to use it.

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Invalid manifest file

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Invisible chars

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License change

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License exception

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Long strings

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Major refactor

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Known malware

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Manifest confusion

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Medium CVE

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Low CVE

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Minified code

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Misc. License Issues

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Non-existent author

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Missing dependency

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Missing license

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Missing package tarball

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Mixed license

Package contains a modified version of an SPDX license exception. Please read carefully before using this code.

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Modified license exception

Package contains a modified version of an SPDX license. Please read carefully before using this code.

@metamask/permission-controller

`@metamask/permission-controller`

Installation

Understanding

Contributing

Keywords

Related posts

@metamask/permission-controller

Installation

Understanding

Contributing

Keywords

Related posts

Trivy Under Attack Again: Widespread GitHub Actions Tag Compromise Exposes CI/CD Secrets

ENISA Publishes Technical Advisory on Secure Use of Package Managers