Cross-site scripting (XSS) vulnerability in the will_paginate gem before 3.0.5 for Ruby allows remote attackers to inject arbitrary web script or HTML via vectors involving generated pagination links.
Cross-Site Scripting (XSS) vulnerabilities in the will_paginate Ruby gem, if exploited, allow attackers to inject malicious scripts into web pages, potentially leading to account compromise, data theft, or website defacement. This vulnerability targets the generation of pagination links, enabling attackers to craft specially designed URLs to execute arbitrary code within a user's browser.
Step 1: Crafting the Malicious Payload: The attacker constructs a URL containing a malicious JavaScript payload within a parameter used by will_paginate to generate pagination links. This payload is designed to execute arbitrary code when the link is clicked.
Step 2: Payload Delivery: The attacker distributes the crafted URL through various means, such as phishing emails, social media, or by embedding it within a compromised website.
Step 3: User Interaction: A user clicks on the malicious URL, typically unaware of the embedded script.
Step 4: Server-Side Processing: The vulnerable web application, using the will_paginate gem, processes the URL, including the attacker-injected payload.
Step 5: Pagination Link Generation: The gem generates pagination links, incorporating the attacker's payload without proper escaping.
Step 6: Rendering in the Browser: The generated pagination link, containing the malicious JavaScript, is rendered in the user's browser.
Step 7: Payload Execution: When the user clicks the crafted link, the browser executes the embedded JavaScript payload within the context of the vulnerable website.
The vulnerability stems from insufficient input sanitization within the will_paginate gem when generating pagination links. Specifically, the gem fails to properly escape user-supplied input used in the construction of these links. This allows an attacker to inject malicious JavaScript code into the link parameters. When a user clicks on a crafted pagination link, the injected script executes within the context of the vulnerable website, enabling the attacker to perform actions on behalf of the user. The root cause is a lack of proper output encoding or input validation of parameters used in pagination link generation, leading to reflected XSS.