CVE-2004-0326 in Professional Gatekeeper
Summary
by MITRE
Buffer overflow in the web proxy for GateKeeper Pro 4.7 allows remote attackers to execute arbitrary code via a long GET request.
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Analysis
by VulDB Data Team • 09/30/2025
The vulnerability identified as CVE-2004-0326 represents a critical buffer overflow flaw within the web proxy component of GateKeeper Pro 4.7, a network security solution designed to provide web filtering and access control. This vulnerability exists in the proxy server implementation where insufficient input validation occurs when processing http get requests, creating a condition where malicious actors can exploit memory corruption to gain unauthorized system access. The flaw specifically manifests when the proxy server receives a specially crafted GET request containing an excessive amount of data that exceeds the allocated buffer space, leading to potential memory overwrite conditions that can be leveraged for code execution.
The technical implementation of this vulnerability stems from improper bounds checking within the proxy server's request handling mechanism. When processing http get requests, the software fails to adequately validate the length of the requested resource identifier, allowing an attacker to craft a request that exceeds the predetermined buffer size allocated for storing the request data. This buffer overflow condition occurs at the application level within the proxy server component, where the system attempts to copy user-supplied data into a fixed-size memory buffer without proper bounds verification. The vulnerability aligns with CWE-121, which describes heap-based buffer overflow conditions, and represents a classic example of unsafe memory handling practices that have been documented extensively in cybersecurity literature. The attack vector operates entirely over the network without requiring authentication, making it particularly dangerous as it can be exploited by remote adversaries.
The operational impact of this vulnerability extends beyond simple code execution to encompass complete system compromise and potential data breaches. Successful exploitation allows remote attackers to execute arbitrary code with the privileges of the proxy server process, which typically runs with elevated permissions to manage network traffic and enforce access controls. This presents a significant risk to organizations relying on GateKeeper Pro for network security, as attackers could potentially bypass the very protections the software is designed to provide. The vulnerability could enable attackers to establish persistent backdoors, redirect traffic through malicious proxies, or access sensitive network resources that would otherwise be protected by the proxy server's filtering capabilities. From an attacker's perspective, this represents a high-value target within the network security infrastructure, as it provides a pathway to circumvent the security controls that protect the organization's network perimeter.
Organizations affected by this vulnerability should implement immediate mitigations including patching the GateKeeper Pro software to the latest available version that addresses the buffer overflow condition, applying network segmentation to limit access to the proxy server, and implementing intrusion detection systems to monitor for suspicious GET request patterns. The mitigation strategy should also include disabling unnecessary proxy functionality and configuring proper input validation at multiple network layers. From a compliance perspective, this vulnerability would likely trigger security assessments under frameworks such as pci dss, which mandates protection against buffer overflow vulnerabilities, and iso 27001, which requires organizations to maintain robust vulnerability management processes. Additionally, security teams should conduct thorough network monitoring to detect potential exploitation attempts and establish incident response procedures to address successful attacks. The vulnerability demonstrates the critical importance of proper input validation and memory management practices in network security software, aligning with attack techniques documented in the mitre att&ck framework under the execution and privilege escalation categories.