Cross Origin Resource Sharing Not Implemented

Cross-Origin Resource Sharing (CORS) is a mechanism that uses additional HTTP header to let the browser know that an application is running from one domain (Origin) and has permission to access resources from another origin (Server). The Cross-Origin Resource Sharing is not found on many of the servers. This enables the web browser to perform cross-domain request using XMLHTTPRequest L2 API. The lack of Cross-Origin Resource Sharing leads to access to sensitive data.

Example

Consider a frontend script code for a web application served from http://example.beaglesecurity.com uses XMLHttpRequest to make a request for http://api.example.beaglesecurity.com/data.json.

Impact

The major impact includes code injection attacks. Code injection is the exploitation of a computer bug which includes processing invalid data.

Mitigation / Precaution

Beagle recommends the following fixes:-

• Try to implement the Cross Origin Resource Sharing

Written by

Rejah Rehim

Co-founder, Director

Rejah brings more than 12 years of industry experience in Information Technology. He is a fervent security enthusiast and serves as a Project Leader at OWASP Foundation, and Commander (Hon.) at Kerala Police. He has authored two books titled “Effective Python Penetration Testing” and “Python Penetration Testing Cookbook” and is the creator of 9 Mozilla add-ons.