Overview
The CVE-2025-6504 vulnerability is a critical security flaw that affects versions of HDP Server below 4.6.2.2978 on Linux. This vulnerability, involving unauthorized access through IP spoofing, poses a serious threat for system administrators and users alike. The exploit leverages the X-Forwarded-For (XFF) header, a client-controlled element, to bypass IP restrictions. While a successful attack would still require valid user credentials, it significantly lowers the barriers to unauthorized access, potentially leading to system compromise or data leakage.
Vulnerability Summary
CVE ID: CVE-2025-6504
Severity: High (CVSS: 8.4)
Attack Vector: Network
Privileges Required: Low
User Interaction: None
Impact: Potential system compromise or data leakage
Affected Products
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Product | Affected Versions
HDP Server | Versions below 4.6.2.2978
How the Exploit Works
The exploit hinges on the X-Forwarded-For (XFF) header, a de facto standard for identifying the originating IP address of a client connecting to a web server through an HTTP proxy. This header is client-controlled, meaning that an attacker could spoof it, and if the spoofed IP matches a whitelisted range, unauthorized access could be granted. Therefore, despite IP restrictions, the system becomes vulnerable to potential unauthorized access.
Conceptual Example Code
Here’s a conceptual example of how the vulnerability might be exploited:
GET /restricted/resource HTTP/1.1
Host: vulnerable-server.com
X-Forwarded-For: <spoofed IP>
User-Agent: Mozilla/5.0 (Windows NT 10.0; Win64; x64)
Authorization: Bearer <valid user token>In this example, the attacker is using a spoofed IP address in the X-Forwarded-For header to trick the server into thinking the request is coming from a trusted network. The presence of a valid user token (which could have been obtained through other means) makes this attack more likely to succeed.
Recommended Mitigation
As a solution, users of HDP Server versions below 4.6.2.2978 should apply the vendor patch immediately. If immediate patching is not feasible, using a Web Application Firewall (WAF) or an Intrusion Detection System (IDS) can serve as temporary mitigation. These tools can help detect and prevent unauthorized access attempts. Long term, however, patching the system should be considered the definitive solution.