CVE-2019-18996 in PB610 Panel Builder 600
Summary
by MITRE
Path settings in HMIStudio component of ABB PB610 Panel Builder 600 versions 2.8.0.424 and earlier accept DLLs outside of the program directory, potentially allowing an attacker with access to the local file system the execution of code in the application�s context.
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Analysis
by VulDB Data Team • 03/15/2024
The vulnerability identified as CVE-2019-18996 affects the HMIStudio component within ABB PB610 Panel Builder 600 software versions 2.8.0.424 and earlier. This issue represents a critical path traversal and dynamic link library loading flaw that undermines the security boundaries of the application. The vulnerability stems from improper handling of dynamic library loading mechanisms within the HMIStudio component, which fails to restrict the search path for DLL files to only the application's designated directories. This design flaw allows attackers with local file system access to manipulate the application's execution flow by placing malicious DLL files in locations outside the program directory, thereby bypassing normal security controls.
The technical implementation of this vulnerability involves the application's failure to properly validate and restrict the dynamic loading of shared libraries. When the HMIStudio component attempts to load required DLLs, it follows a predictable search order that includes directories outside the application's installation folder. This behavior creates an opportunity for privilege escalation attacks where an attacker can place a malicious DLL with the same name as a legitimate library in a directory that gets searched before the application's own directory. The vulnerability is classified under CWE-426 as an Untrusted Search Path, which directly relates to the improper handling of library loading mechanisms and path resolution. This flaw aligns with ATT&CK technique T1059.001 for Command and Scripting Interpreter, as it enables code execution through manipulation of the application's runtime environment.
The operational impact of this vulnerability is severe for industrial control systems and automation environments where ABB PB610 Panel Builder 600 is deployed. An attacker with local access to the system can execute arbitrary code within the context of the HMIStudio application, potentially gaining elevated privileges and access to sensitive industrial control data. This represents a significant threat to operational technology environments where the application may run with elevated privileges or have access to critical control system information. The vulnerability affects the integrity and availability of industrial automation processes, as malicious code execution could disrupt normal operations or provide unauthorized access to control system functions. The attack surface is particularly concerning in environments where physical security controls may be insufficient, as local access can often be achieved through various means including social engineering, insider threats, or compromised credentials.
Mitigation strategies for CVE-2019-18996 should focus on both immediate remediation and long-term architectural improvements. The most effective immediate solution involves applying the vendor-supplied patches or updates that address the path traversal vulnerability in the HMIStudio component. Organizations should also implement strict access controls and privilege separation to limit local file system access to the application directory. The principle of least privilege should be enforced by ensuring that the application runs with minimal required permissions and that DLL loading is restricted to specific, trusted directories. Network segmentation and monitoring should be implemented to detect unauthorized file system modifications and suspicious DLL loading activities. Additionally, regular security assessments should be conducted to identify similar path traversal vulnerabilities in other industrial control system components, as this type of flaw is particularly prevalent in legacy industrial software environments where security considerations may not have been prioritized during initial development phases.