Source: secalert@redhat.com
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.
Remote attackers can inject malicious scripts into web pages using the will_paginate gem, potentially leading to account compromise and data theft. This vulnerability, present in older versions of the gem, allows attackers to execute arbitrary code within a user's browser through crafted pagination links, impacting the confidentiality and integrity of web applications.
Step 1: Vulnerability Identification: The attacker identifies a web application using the vulnerable will_paginate gem.
Step 2: Payload Crafting: The attacker crafts a malicious payload containing JavaScript code or HTML tags designed to exploit the XSS vulnerability. This payload is typically embedded within a specially crafted pagination link.
Step 3: Payload Delivery: The attacker delivers the malicious pagination link to a target user. This could be through phishing emails, social engineering, or by injecting the link into a forum or comment section of the vulnerable website.
Step 4: User Interaction: The target user clicks on the malicious pagination link.
Step 5: Code Execution: The web browser renders the pagination link, including the attacker's injected code. The browser then executes the malicious JavaScript code within the context of the vulnerable website.
Step 6: Attack Execution: The injected JavaScript code can perform various malicious actions, such as stealing user credentials (e.g., cookies), redirecting the user to a phishing site, or defacing the 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 to construct these links. This allows an attacker to inject malicious HTML or JavaScript code into the pagination links. When a user clicks on a crafted link, the injected script executes within the context of the vulnerable website, enabling cross-site scripting (XSS) attacks. The root cause is a lack of proper output encoding or escaping of user-controlled parameters before they are included in the generated HTML. This allows for the injection of arbitrary HTML tags, including <script> tags, which can then execute malicious JavaScript code in the user's browser. The flaw is not a buffer overflow or a race condition, but rather a failure to properly sanitize user input before rendering it in the HTML output.
While no specific APTs are directly linked to this specific CVE, the nature of XSS vulnerabilities makes them attractive to a wide range of attackers, including those seeking to steal credentials, deface websites, or conduct other malicious activities. Not listed on CISA KEV.
Network Intrusion Detection Systems (IDS) can be configured to detect malicious JavaScript code or HTML tags within HTTP requests and responses, particularly within pagination link parameters.
Web Application Firewalls (WAFs) can be used to filter out malicious payloads in HTTP requests, blocking attempts to inject XSS code.
Security Information and Event Management (SIEM) systems can be configured to analyze web server logs for suspicious activity, such as unusual HTTP requests containing XSS payloads.
Monitor web server logs for unusual HTTP requests containing potentially malicious JavaScript or HTML within pagination parameters (e.g., page, per_page).
Examine the source code of web pages for any instances of unsanitized user input being directly rendered in the HTML output, particularly within pagination links.
Upgrade the will_paginate gem to version 3.0.5 or later.
Implement proper input validation and output encoding (escaping) for all user-supplied data, especially when generating HTML content.
Use a robust HTML escaping library to sanitize user input before rendering it in the HTML output.
Employ a Content Security Policy (CSP) to restrict the sources from which the browser can load resources (e.g., scripts, stylesheets). This can mitigate the impact of XSS attacks by preventing the execution of malicious scripts.
Regularly scan the application for vulnerabilities using static and dynamic analysis tools.
Implement a WAF to filter malicious requests.
Educate developers on secure coding practices, including how to prevent XSS vulnerabilities.