CVE-2009-0802 in WinGate
Summary
by MITRE
Qbik WinGate, when transparent interception mode is enabled, uses the HTTP Host header to determine the remote endpoint, which allows remote attackers to bypass access controls for Flash, Java, Silverlight, and probably other technologies, and possibly communicate with restricted intranet sites, via a crafted web page that causes a client to send HTTP requests with a modified Host header.
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Analysis
by VulDB Data Team • 04/26/2025
The vulnerability described in CVE-2009-0802 affects Qbik WinGate software when operating in transparent interception mode, representing a significant security flaw that undermines network access controls and potentially exposes internal resources to external threats. This issue stems from the software's reliance on the HTTP Host header to determine the destination endpoint for intercepted traffic, creating a pathway for malicious actors to manipulate network communications through crafted web pages that modify HTTP headers. The vulnerability specifically impacts the software's ability to properly authenticate and authorize access to various web technologies including Flash, Java, and Silverlight applications.
The technical implementation of this flaw occurs within WinGate's transparent proxy interception mechanism where the application processes HTTP requests and uses the Host header field to route traffic to appropriate destinations. When attackers craft malicious web pages that modify the Host header in HTTP requests, they can redirect traffic intended for external websites to internal network resources that would normally be restricted. This occurs because the system does not properly validate or sanitize the Host header values against authorized access controls, allowing unauthorized access to internal services that should remain protected from external network access. The vulnerability is particularly dangerous because it operates at the network layer where traffic interception and routing decisions are made, effectively bypassing traditional network security controls.
The operational impact of this vulnerability extends beyond simple access control bypass to potentially enable unauthorized communication with restricted intranet sites, creating a serious risk for organizations that rely on WinGate for network security. Attackers can exploit this flaw to gain access to internal web applications, databases, or other network services that are typically protected by firewalls or other access control mechanisms. This represents a critical security gap in the software's architecture, as it allows remote attackers to perform unauthorized network reconnaissance and potentially execute further attacks against internal systems. The vulnerability's scope includes not just the direct access to internal resources but also the potential for establishing persistent access channels that could remain undetected for extended periods.
Organizations using Qbik WinGate in transparent interception mode should immediately implement mitigations that include disabling the vulnerable transparent interception functionality or implementing strict Host header validation controls. The solution involves configuring the proxy software to validate Host header values against predefined authorized domains or implementing additional authentication mechanisms that do not rely solely on the HTTP Host header for routing decisions. Security professionals should also consider implementing network segmentation and additional monitoring controls to detect anomalous traffic patterns that might indicate exploitation attempts. This vulnerability aligns with CWE-284 Access Control Issues, specifically addressing improper access control through header manipulation, and represents a technique that could be categorized under ATT&CK tactic TA0011 Command and Control through unauthorized network communication. The fix typically requires either patching the software to properly validate Host headers or reconfiguring the proxy settings to avoid the vulnerable interception mode entirely.