CVE-2002-1643 in Helix Universal Server
Summary
by MITRE
Multiple buffer overflows in RealNetworks Helix Universal Server 9.0 (9.0.2.768) allow remote attackers to execute arbitrary code via (1) a long Transport field in a SETUP RSTP request, (2) a DESCRIBE RSTP request with a long URL argument, or (3) two simultaneous HTTP GET requests with long arguments.
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Analysis
by VulDB Data Team • 09/03/2025
The vulnerability described in CVE-2002-1643 represents a critical security flaw in RealNetworks Helix Universal Server version 9.0, specifically affecting the 9.0.2.768 release. This issue manifests as multiple buffer overflow conditions that can be exploited remotely to achieve arbitrary code execution on the affected system. The vulnerability affects the server's handling of various Real Time Streaming Protocol (RSTP) and HTTP requests, making it particularly dangerous as it can be triggered through different attack vectors. The buffer overflows occur in the server's processing of client requests, where insufficient input validation allows attackers to craft malicious payloads that exceed the allocated buffer space, leading to memory corruption and potential code execution.
The technical implementation of this vulnerability involves three distinct attack vectors that exploit different areas of the server's request processing logic. The first vector targets the Transport field within SETUP RSTP requests, where an attacker can send a malformed request containing an excessively long transport parameter that overflows the server's buffer. The second vector exploits the DESCRIBE RSTP request handling, specifically when processing a long URL argument that exceeds the buffer capacity allocated for URL parsing. The third vector involves two simultaneous HTTP GET requests with long arguments, which can cause buffer overflows in the server's HTTP request processing module. These vulnerabilities fall under the common weakness enumeration CWE-121, which describes heap-based buffer overflow conditions, and are particularly dangerous due to their potential for remote code execution.
The operational impact of CVE-2002-1643 is severe and multifaceted, as it allows remote attackers to gain complete control over affected servers without requiring authentication. Successful exploitation can result in unauthorized access to media streams, data exfiltration, server compromise, and potential use as a pivot point for further attacks within a network infrastructure. The vulnerability affects organizations that rely on RealNetworks Helix Universal Server for media streaming services, potentially exposing them to significant security risks including service disruption, unauthorized content access, and full system compromise. Given the nature of streaming servers, attackers could leverage these vulnerabilities to manipulate media content, redirect traffic, or establish persistent access points within the network environment.
Mitigation strategies for this vulnerability should focus on immediate patching and system hardening measures. Organizations must upgrade to a patched version of RealNetworks Helix Universal Server that addresses these buffer overflow conditions. Additionally, network segmentation and access controls should be implemented to limit exposure of streaming servers to untrusted networks. The use of intrusion detection systems and monitoring tools can help detect exploitation attempts through abnormal request patterns or unusual traffic behavior. From an ATT&CK framework perspective, this vulnerability maps to techniques involving remote code execution through protocol manipulation and buffer overflow exploitation. Network administrators should also consider implementing rate limiting and input validation controls on streaming protocol endpoints to reduce the attack surface. Regular security assessments and vulnerability scanning should be conducted to identify similar issues in other streaming or media server implementations within the organization's infrastructure.