CVE-2003-0317

Step 1: Target Identification: The attacker identifies a web server running iisPROTECT 2.1 or 2.2.

Step 2: Crafting the Malicious Request: The attacker constructs an HTTP request targeting a protected resource, such as a restricted file or directory.

Step 3: URL Encoding: The attacker strategically encodes characters within the request's URL using URL encoding (e.g., %20 for space, %2e%2e for ../). This encoding is designed to bypass the authentication filter.

Step 4: Request Submission: The attacker sends the crafted HTTP request to the vulnerable web server.

Step 5: Authentication Bypass: iisPROTECT's authentication filter fails to correctly decode and validate the URL-encoded characters. The filter incorrectly processes the request, allowing the attacker to bypass the authentication checks.

Step 6: Unauthorized Access: The attacker gains unauthorized access to the protected resource, potentially leading to data exfiltration or system compromise.

The vulnerability stems from improper handling of URL-encoded characters by the iisPROTECT software. The software's authentication mechanism fails to correctly decode and validate these characters before processing the request. Specifically, the software likely uses a flawed string comparison or parsing function that doesn't account for all possible URL encoding variations. This allows attackers to craft malicious requests that appear legitimate to the authentication filter, bypassing access controls. The root cause is a lack of robust input validation and sanitization, leading to a logical flaw in the authentication process. The software's parsing logic likely fails to normalize the input, allowing for variations in encoding that bypass intended security checks.