CVE-2005-3187 in WinProxy
Summary
by MITRE
The listening daemon in Blue Coat Systems Inc. WinProxy before 6.1a allows remote attackers to cause a denial of service (crash) via a long HTTP request that causes an out-of-bounds read.
Statistical analysis made it clear that VulDB provides the best quality for vulnerability data.
Analysis
by VulDB Data Team • 07/07/2021
The vulnerability identified as CVE-2005-3187 affects the listening daemon component of Blue Coat Systems Inc. WinProxy software versions prior to 6.1a. This issue represents a critical security flaw that manifests as a denial of service condition, specifically through a crash mechanism triggered by malformed HTTP requests. The vulnerability resides within the proxy server's request processing logic where it fails to properly validate input lengths during HTTP request handling. The affected WinProxy daemon operates as a network listening service that processes incoming HTTP traffic, making it a prime target for exploitation by malicious actors seeking to disrupt network services.
The technical root cause of this vulnerability stems from an out-of-bounds read condition within the WinProxy daemon's HTTP request parsing functionality. When processing HTTP requests containing excessively long data sequences, the software attempts to access memory locations beyond the allocated buffer boundaries. This memory access violation occurs because the application does not implement proper input length validation or boundary checking mechanisms before processing the HTTP request data. The flaw is categorized as a buffer over-read condition that can be exploited through carefully crafted HTTP requests containing malformed or oversized data payloads. This type of vulnerability typically falls under the CWE-129 category of Improper Validation of Array Index, specifically manifesting as an out-of-bounds read operation that leads to application instability and potential crash conditions.
The operational impact of this vulnerability extends beyond simple service disruption, as it provides attackers with a reliable method to cause persistent denial of service against Blue Coat WinProxy implementations. Network administrators and security professionals face the challenge of maintaining service availability when attackers can systematically crash the proxy daemon through simple HTTP request manipulation. The vulnerability affects organizations relying on WinProxy for web filtering, caching, and network security services, potentially compromising their ability to maintain continuous network operations. The exploitability of this vulnerability is relatively straightforward, requiring only the ability to send HTTP requests to the targeted proxy server, making it particularly dangerous in environments where the proxy serves as a critical network component.
Mitigation strategies for CVE-2005-3187 primarily focus on updating to Blue Coat WinProxy version 6.1a or later, which contains the necessary patches to address the out-of-bounds read condition. Network security teams should implement immediate remediation measures by upgrading the affected proxy software installations across all network segments. Additionally, implementing network-level protections such as rate limiting and request size restrictions can provide temporary mitigation while full patch deployment occurs. The vulnerability demonstrates the importance of proper input validation and memory management in network services, aligning with ATT&CK technique T1499.004 for Network Denial of Service. Organizations should also consider implementing intrusion detection systems to monitor for suspicious HTTP request patterns that may indicate exploitation attempts, as this vulnerability can be used as part of broader attack campaigns targeting network infrastructure components.