Overview
CVE-2024-5540 describes a reflective cross-site scripting (XSS) vulnerability affecting ALC WebCTRL and Carrier i-Vu building automation systems in versions older than 8.0. This vulnerability resides within the login panels of these systems. Successful exploitation could allow a malicious actor to compromise the client browser of a user accessing the affected login page. This could lead to session hijacking, credential theft, or other malicious activities.
Technical Details
The vulnerability is a reflective XSS, meaning the malicious script is embedded within a crafted URL. When a user clicks on this malicious link and visits the vulnerable login page, the script is executed in their browser context. The vulnerability exists because user-supplied input is not properly sanitized or encoded before being included in the generated HTML output of the login page. Attackers can inject arbitrary JavaScript code into the application, which then gets executed by the victim’s browser.
CVSS Analysis
Unfortunately, a CVSS score is not currently available for CVE-2024-5540. A thorough risk assessment should be conducted based on your specific environment and the criticality of the affected ALC WebCTRL or Carrier i-Vu system.
Possible Impact
The impact of this vulnerability can be significant. An attacker could:
- Steal user credentials: Capture usernames and passwords used to log into the ALC WebCTRL or Carrier i-Vu system.
- Hijack user sessions: Gain unauthorized access to the system with the privileges of the logged-in user.
- Deface the login page: Modify the appearance of the login page to phish for credentials or spread misinformation.
- Redirect users to malicious websites: Redirect users to a fake login page or other malicious websites to steal their information.
- Execute arbitrary code: In certain circumstances, execute arbitrary code on the user’s machine (though this is less common with XSS, it’s a potential escalation point).
Mitigation or Patch Steps
The primary mitigation is to upgrade your ALC WebCTRL or Carrier i-Vu system to version 8.0 or later. This version should include the necessary fixes to address the XSS vulnerability. Contact Carrier directly for upgrade information and support.
- Upgrade to the latest version: The most effective solution is to upgrade to version 8.0 or a later patched release.
- Web Application Firewall (WAF): Implement a WAF to filter out malicious requests and prevent XSS attacks. Configure the WAF with rules to detect and block common XSS patterns.
- Input Validation: Ensure all user inputs are properly validated and sanitized. Use appropriate encoding functions to prevent the execution of malicious code. This is something the software vendor must implement.
- Principle of Least Privilege: Grant users only the minimum necessary permissions to access and manage the building automation system.
- Regular Security Audits: Perform regular security audits and penetration testing to identify and address vulnerabilities in your systems.
