Proofpoint Collaboration Protection integrates URL Defense technology to provide real-time, time-of-click protection against malicious links shared in collaboration tools. When a user clicks a URL, it is analyzed by Proofpoint's threat intelligence services. If the destination is identified as malicious (e.g., a phishing site or malware download page), the user's browser is automatically and transparently redirected to a secure, customizable block page. This action prevents the user from accessing the harmful content and mitigates the threat instantly.

A. Sending an alert to a manager is a potential secondary notification, not the primary, real-time protective action taken for the user.

B. Encrypting a browser session (e.g., with TLS/SSL) secures data in transit but does not prevent access to a malicious website.

C. While the message containing the URL may be removed or quarantined, the immediate action upon a user's click is the browser redirection.

1. Proofpoint, Inc. Proofpoint Collaboration Protection Data Sheet. The document highlights the capability to "Stop threats in collaboration tools" using "time-of-click URL sandboxing" which blocks access to malicious links.

2. Proofpoint, Inc. URL Defense Data Sheet. This document details the core technology, explaining that it "rewrites URLs" and "blocks clicks to malicious web pages" by redirecting to a block page.