Specify origin in postMessage

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Metadata

ID: javascript-browser-security/postmessage-permissive-origin

Language: JavaScript

Severity: Warning

Category: Security

CWE: 923

Description

Always specify the origin of the message for security reasons and to avoid spoofing attacks. Always specify an exact target origin, not *, when you use postMessage to send data to other windows.

Learn More

window.postMessage documentation

Non-Compliant Code Examples

window.postMessage(message, '*')

Compliant Code Examples

window.postMessage(message, 'https://app.domain.tld')

How to use this rule

1
2
rulesets:
  - javascript-browser-security     # Rules to enforce JavaScript browser security.

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