Overview
The Common Vulnerabilities and Exposures (CVE) system has recently identified a critical cybersecurity vulnerability, CVE-2025-55420, that seriously threatens the security of websites running FoxCMS v1.2.6. This blog post delves into the specifics of this vulnerability, its potential impact, and what measures can be taken to mitigate it. Being a reflected Cross Site Scripting (XSS) vulnerability, it exposes users and networks to potential system compromise and data leakage, emphasizing the importance of immediate remedial action.
Vulnerability Summary
CVE ID: CVE-2025-55420
Severity: High (8.8 CVSS Score)
Attack Vector: Network
Privileges Required: None
User Interaction: Required
Impact: Potential system compromise or data leakage
Affected Products
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Product | Affected Versions
FoxCMS | v1.2.6
How the Exploit Works
The vulnerability lies within the /index.php of FoxCMS v1.2.6. A crafted script sent via a GET request to this index page is reflected unsanitized into the HTML response. This means that the arbitrary JavaScript code embedded in the GET request is executed when a logged-in user submits the malicious input. Essentially, this vulnerability allows an attacker to inject malicious scripts into otherwise benign and trusted websites.
Conceptual Example Code
Below is a conceptual example of how the vulnerability might be exploited. An attacker sends a malicious script embedded in a GET request to the /index.php page:
GET /index.php?payload=<script>malicious_code_here</script> HTTP/1.1
Host: vulnerable-website.comWhen a logged-in user loads the affected page, the malicious script is executed in their browser. This could lead to various outcomes, such as stealing session cookies, performing actions on behalf of the user, or even delivering a payload for further exploitation.
Mitigation and Prevention
To mitigate this vulnerability, it is highly recommended that users apply the vendor patch as soon as it is available. As a temporary measure, a Web Application Firewall (WAF) or Intrusion Detection System (IDS) can be used to identify and block attempts to exploit this vulnerability. Regularly updating and patching software, as well as implementing robust security measures such as WAF and IDS, can go a long way in preventing such vulnerabilities from being exploited.
