Permissive origin in postMessage

• Rule ID: javascript_lang_post_message_origin
• Languages: javascript
• Source: post_message_origin.yml

Description

Using "*" (any) as the target origin of a postMessage call allows third-parties to read the message.

Remediations

❌ Avoid using "*" as the target origin:

window.postMessage(message, '*')

✅ Specify the origin for your target application:

window.postMessage(message, 'https://myapp.example.com')

Associated CWE

• CWE-346: Origin Validation Error

OWASP Top 10

• A07:2021 - Identification and Authentication Failures

Configuration

To skip this rule during a scan, use the following flag

bearer scan /path/to/your-project/ --skip-rule=javascript_lang_post_message_origin

To run only this rule during a scan, use the following flag

bearer scan /path/to/your-project/ --only-rule=javascript_lang_post_message_origin