CVE-2012-3847 in Wonderware Application Server
Summary
by MITRE
slssvc.exe in Invensys Wonderware SuiteLink in Invensys InTouch 2012 and Wonderware Application Server 2012 allows remote attackers to cause a denial of service (resource consumption) via a long Unicode string, a different vulnerability than CVE-2012-3007.
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Analysis
by VulDB Data Team • 01/24/2018
The vulnerability identified as CVE-2012-3847 affects the slssvc.exe service component within Invensys Wonderware SuiteLink, specifically impacting Invensys InTouch 2012 and Wonderware Application Server 2012 products. This issue represents a denial of service vulnerability that stems from improper handling of Unicode input strings by the SuiteLink service, which operates as a critical component for industrial automation and control system communications. The vulnerability is particularly concerning within industrial control environments where system availability and reliability are paramount for operational continuity. The flaw manifests when the service receives a specially crafted long Unicode string, causing it to consume excessive system resources and ultimately leading to service disruption.
The technical root cause of this vulnerability lies in the inadequate input validation and string processing mechanisms within the slssvc.exe service. When processing Unicode strings of excessive length, the service fails to implement proper bounds checking or resource allocation limits, resulting in uncontrolled memory consumption and potential system resource exhaustion. This behavior aligns with CWE-122, which describes improper restriction of operations within a limited memory buffer, and represents a classic example of resource exhaustion through malformed input processing. The vulnerability operates at the application layer, specifically targeting the service communication protocols used by Wonderware SuiteLink for industrial automation data exchange. Attackers can exploit this weakness by sending carefully constructed Unicode payloads to the affected service, causing it to consume increasing amounts of memory and processing power until the system becomes unresponsive or crashes.
The operational impact of CVE-2012-3847 extends beyond simple service disruption to potentially compromise industrial control system integrity and operational continuity. In manufacturing and process control environments where Wonderware products are commonly deployed, such a vulnerability could lead to production halts, safety system failures, or cascading operational issues that affect entire facilities. The remote nature of the attack means that threat actors can exploit this vulnerability from external networks without requiring physical access to the industrial control systems, making it particularly dangerous in environments where network segmentation is not properly implemented. This vulnerability also aligns with ATT&CK technique T1499.004, which covers network denial of service attacks, and represents a significant risk to industrial cybersecurity posture. The resource consumption aspect of this vulnerability can potentially be leveraged to create persistent service degradation that may be difficult to detect and remediate in industrial environments where system monitoring may be limited or specialized.
Mitigation strategies for CVE-2012-3847 should focus on both immediate protective measures and long-term architectural improvements. Organizations should implement network segmentation to limit access to the affected Wonderware services, particularly restricting communication to only trusted networks and systems. Applying the vendor-provided security patches and updates is essential for addressing the root cause of the vulnerability, though organizations should verify that patching does not introduce compatibility issues with existing industrial control system configurations. Network-based intrusion detection systems should be configured to monitor for unusual traffic patterns or large Unicode string transmissions that may indicate exploitation attempts. Additionally, implementing input validation controls at network boundaries and application levels can help prevent malformed Unicode strings from reaching the vulnerable service components. System administrators should also consider implementing service monitoring and alerting mechanisms to detect resource consumption anomalies that may indicate exploitation attempts. The vulnerability highlights the importance of maintaining up-to-date security practices in industrial environments and underscores the need for comprehensive vulnerability management programs that address both traditional IT security concerns and industrial control system specific risks.