💰 Estimated Savings: CYVOCATE’s report helped prevent potential financial & reputational losses exceeding $250,000+ due to unauthorized access to restricted functionality.

Introduction

At CYVOCATE, we often uncover subtle authorization flaws that attackers can exploit with simple manipulation techniques.

In this engagement, we identified and exploited a response manipulation vulnerability where client-side trust in HTTP status codes enabled bypassing restricted access. By modifying responses in transit, we gained access to restricted admin functionality, which—if left unfixed—could have resulted in account takeovers and sensitive data exposure.

Discovery Process

Step 1: Targeting Restricted Resources

The /admin panel returned:

HTTP/2 401 Unauthorized
{"message":"Authentication required"}

This indicated server-side restrictions were in place—but only partially.

Step 2: Response Manipulation

Using Burp Proxy, we intercepted the response and modified:

HTTP/2 401 Unauthorized

to:

HTTP/2 200 OK

Forwarding the manipulated response allowed partial access to the Admin Panel, bypassing the intended authentication flow.

Step 3: Assessing Impact

While not a full compromise, the flaw enabled: