CVE-2011-4534 in zenon
Summary
by MITRE
ZenSysSrv.exe in Ing. Punzenberger COPA-DATA zenon 6.51 SP0 allows remote attackers to cause a denial of service (service crash) or possibly execute arbitrary code via a series of connections and disconnections on TCP port 1101, aka Reference Number 25212.
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Analysis
by VulDB Data Team • 03/27/2019
The vulnerability identified as CVE-2011-4534 affects ZenSysSrv.exe component within Ing. Punzenberger COPA-DATA zenon 6.51 SP0 industrial automation software. This represents a critical security flaw that exposes the system to both denial of service attacks and potential remote code execution capabilities. The vulnerability manifests through improper handling of network connections on TCP port 1101, which serves as the primary communication channel for the zenon software's system services. The affected software operates within industrial control environments where reliability and security are paramount, making this vulnerability particularly concerning for operational technology infrastructure.
The technical flaw stems from insufficient input validation and connection management within the ZenSysSrv.exe process. When remote attackers establish and subsequently terminate multiple connections to TCP port 1101 in rapid succession, the service fails to properly manage memory allocation and connection state tracking. This leads to memory corruption issues that can result in service crashes or more severe conditions that allow arbitrary code execution. The vulnerability operates at the transport layer protocol level and demonstrates poor error handling mechanisms that fail to gracefully process malformed or excessive connection sequences. According to CWE classification, this vulnerability maps to CWE-121, which addresses stack-based buffer overflow conditions, and CWE-122, concerning heap-based buffer overflow scenarios that can occur during improper memory management.
The operational impact of this vulnerability extends beyond simple service disruption to potentially compromise entire industrial control systems. In industrial environments where zenon software manages critical infrastructure monitoring and control, a successful exploitation could lead to unauthorized access to operational data, modification of control parameters, or complete system compromise. The vulnerability's remote nature means attackers can exploit it from external networks without requiring physical access to the industrial facilities. This aligns with ATT&CK technique T1190, which describes exploitation of remote services, and T1059, covering execution through command and scripting interpreters. The potential for remote code execution places this vulnerability in the high-risk category for industrial cybersecurity, particularly in sectors such as manufacturing, energy, and process control where system availability and integrity are mission-critical.
Organizations utilizing COPA-DATA zenon 6.51 SP0 must implement immediate mitigations to protect their industrial environments from exploitation. The primary recommendation involves applying the vendor-provided security patches and updates as soon as they become available. Network segmentation should be implemented to isolate the affected systems from general network access, restricting TCP port 1101 to trusted administrative networks only. Additionally, implementing network monitoring solutions that can detect unusual connection patterns and rapid connection/disconnection sequences will help identify potential exploitation attempts. The use of intrusion detection systems with signature-based detection for this specific vulnerability should be considered, along with regular security assessments of industrial control systems to identify similar unpatched vulnerabilities. Organizations should also review their operational procedures to ensure that system administrators are trained to recognize and respond to potential exploitation attempts, as the vulnerability's nature may not be immediately apparent through standard monitoring systems.