Multiple cross-site scripting (XSS) vulnerabilities in webacc in Novell GroupWise WebAccess before 7 Support Pack 3 Public Beta allow remote attackers to inject arbitrary web script or HTML via the (1) User.html, (2) Error, (3) User.Theme.index, and (4) and User.lang parameters.
Novell GroupWise WebAccess versions prior to 7 Support Pack 3 Public Beta are vulnerable to multiple cross-site scripting (XSS) attacks. This allows attackers to inject malicious JavaScript into web pages viewed by users, potentially leading to account compromise, session hijacking, and data theft.
Step 1: Payload Delivery: The attacker crafts a malicious URL containing a specially crafted JavaScript payload within one of the vulnerable parameters (e.g., User.html, Error, User.Theme.index, or User.lang).
Step 2: Request Submission: The attacker tricks a user into clicking the malicious URL, or the URL is delivered through another vector (e.g., phishing email).
Step 3: Server Processing: The GroupWise WebAccess server receives the HTTP request containing the malicious URL.
Step 4: Parameter Handling: The server processes the request and retrieves the value of the vulnerable parameter.
Step 5: Response Generation: The server constructs an HTML response, incorporating the value of the vulnerable parameter. Because the input is not sanitized, the malicious JavaScript payload is included in the response.
Step 6: Browser Execution: The user's web browser receives the HTML response containing the malicious JavaScript. The browser then executes the JavaScript within the context of the GroupWise WebAccess domain.
Step 7: Exploitation: The malicious JavaScript executes, potentially allowing the attacker to steal cookies, redirect the user to a phishing site, or perform other malicious actions.
The vulnerability stems from insufficient input validation and output encoding within the webacc application. Specifically, the application fails to properly sanitize user-supplied data passed through the User.html, Error, User.Theme.index, and User.lang parameters. This allows attackers to inject malicious HTML and JavaScript code. The root cause is a lack of proper input validation and output encoding (e.g., HTML entity encoding) when rendering user-provided data within the web application's response. The application trusts user input without sanitizing it, leading to the execution of arbitrary code within the context of the user's browser.