CVE-2002-1999 in Praesidium Webproxy
Summary
by MITRE
HP Praesidium Webproxy 1.0 running on HP-UX 11.04 VVOS could allow remote attackers to cause Webproxy to forward requests to the internal network via crafted HTTP requests.
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Analysis
by VulDB Data Team • 07/07/2024
The vulnerability identified as CVE-2002-1999 represents a significant security flaw in HP Praesidium Webproxy version 1.0 running on HP-UX 11.04 VVOS operating systems. This issue stems from inadequate input validation mechanisms within the web proxy software that fails to properly sanitize or filter incoming HTTP requests. The flaw specifically manifests when the proxy processes malformed or specially crafted HTTP requests that contain unexpected parameters or headers, allowing malicious actors to manipulate the proxy's behavior to forward traffic to internal network resources that should remain protected from external access.
The technical nature of this vulnerability aligns with CWE-20, which describes improper input validation, and demonstrates how insufficient sanitization of user-supplied data can lead to unauthorized access patterns. Attackers can exploit this weakness by crafting HTTP requests that include specific headers or parameters designed to bypass the proxy's normal routing logic, causing the system to forward requests to internal servers that are typically isolated from direct internet access. This creates a path for remote attackers to potentially access internal network services, databases, or other sensitive resources that should only be accessible through controlled internal pathways.
The operational impact of this vulnerability extends beyond simple information disclosure, as it fundamentally compromises the network's security perimeter and trust model. When an attacker successfully exploits this flaw, they effectively gain the ability to perform internal network reconnaissance and potentially escalate their access to critical internal systems. The vulnerability affects organizations that rely on web proxies for network segmentation and access control, as it undermines the very purpose of using a proxy server to isolate internal resources from external threats. This represents a classic case of a man-in-the-middle attack vector where the proxy itself becomes a conduit for unauthorized internal network access rather than a protective barrier.
Mitigation strategies for CVE-2002-1999 should focus on immediate patching of the affected HP Praesidium Webproxy software to the latest available version that contains proper input validation and sanitization mechanisms. Organizations should also implement network segmentation controls and firewall rules that restrict direct access to internal resources from the proxy server, while ensuring that the proxy itself operates with minimal privileges and restricted network access. Additionally, implementing proper HTTP request filtering and monitoring for unusual request patterns can help detect exploitation attempts. The vulnerability's classification under ATT&CK technique T1071.001 for application layer protocol: web protocols highlights the importance of implementing comprehensive network traffic analysis and intrusion detection systems to identify and prevent such exploitation patterns. Regular security assessments and penetration testing should be conducted to verify that proxy configurations properly enforce network isolation principles and that no similar input validation weaknesses exist in other network security appliances.