The Multiple File Upload add-on component 3.1.0 for OutSystems is vulnerable to Unrestricted File Upload. This occurs because file extension and size validations are enforced solely on the client side. An attacker can intercept the upload request and modify a parameter to bypass extension restrictions and upload arbitrary files. NOTE: this is a third-party component that is not supplied or supported by OutSystems.

Outsystems Multiple File Upload < 3.1.0 is vulnerable to Unrestricted File Upload. The vulnerability is because file extension and size validations are enforced solely on the client side. An attacker can intercept the upload request and modify the parameter to bypass extension restrictions and upload arbitrary files.