CVE-2018-8833 in WebAccess HMI Designer
Summary
by MITRE
Heap-based buffer overflow vulnerabilities in Advantech WebAccess HMI Designer 2.1.7.32 and prior caused by processing specially crafted .pm3 files may allow remote code execution.
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Analysis
by VulDB Data Team • 01/31/2020
The vulnerability identified as CVE-2018-8833 represents a critical heap-based buffer overflow in Advantech WebAccess HMI Designer version 2.1.7.32 and earlier releases. This flaw exists within the software's handling of specially crafted .pm3 files, which are used for project management and configuration in industrial human-machine interface systems. The vulnerability architecture stems from inadequate input validation and memory management practices during the parsing of these project files, creating exploitable conditions that could lead to arbitrary code execution.
The technical implementation of this vulnerability involves a heap-based buffer overflow that occurs when the application processes malformed .pm3 files containing oversized data structures or improperly formatted memory allocations. This type of vulnerability falls under the Common Weakness Enumeration category CWE-121, which specifically addresses stack and heap buffer overflow conditions. The flaw manifests when the software attempts to copy data into a heap-allocated buffer without proper bounds checking, allowing attackers to overwrite adjacent memory locations and potentially execute malicious code with the privileges of the affected application.
From an operational perspective, this vulnerability presents significant risks to industrial control systems and manufacturing environments that rely on Advantech WebAccess HMI Designer for operational technology infrastructure. The remote code execution capability means attackers could potentially compromise entire industrial networks without physical access to the systems, making this a particularly dangerous vulnerability in critical infrastructure environments. The attack vector is particularly concerning as it can be initiated through remote file delivery mechanisms, including email attachments, web downloads, or network shares that contain the malicious .pm3 files.
The impact of exploitation extends beyond simple code execution to potentially enable attackers to gain persistent access to industrial control systems, manipulate operational processes, or exfiltrate sensitive operational data. This vulnerability directly aligns with several tactics described in the MITRE ATT&CK framework, particularly those related to initial access through malicious files and privilege escalation within industrial control environments. Organizations utilizing this software in operational technology environments face heightened risk of supply chain attacks or targeted compromises that could disrupt critical manufacturing processes or operational continuity.
Mitigation strategies should focus on immediate software updates to versions that address the buffer overflow conditions, alongside network segmentation to limit access to affected systems. Security professionals should implement strict file validation procedures for .pm3 files and consider deploying network intrusion detection systems to monitor for exploitation attempts. Additionally, organizations should conduct comprehensive vulnerability assessments of their industrial control system environments and establish robust patch management processes specifically tailored for operational technology infrastructure to prevent similar vulnerabilities from occurring in the future.