CVE-2019-6136 in libIEC61850
Summary
by MITRE
An issue has been found in libIEC61850 v1.3.1. Ethernet_setProtocolFilter in hal/ethernet/linux/ethernet_linux.c has a SEGV, as demonstrated by sv_subscriber_example.c and sv_subscriber.c.
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Analysis
by VulDB Data Team • 06/26/2023
The vulnerability identified as CVE-2019-6136 represents a critical memory corruption flaw within the libIEC61850 library version 1.3.1, specifically affecting the Ethernet protocol filtering mechanism. This issue manifests as a segmentation fault occurring in the Ethernet_setProtocolFilter function located within the hal/ethernet/linux/ethernet_linux.c source file. The vulnerability is particularly concerning as it affects the foundational networking capabilities of the library, which is widely used in industrial automation and power systems communication protocols. The flaw becomes apparent when executing the sv_subscriber_example.c and sv_subscriber.c demonstration programs, indicating that the issue is not merely theoretical but has practical exploitation potential within real-world implementations.
The technical root cause of this vulnerability lies in improper input validation and memory management within the Ethernet_setProtocolFilter function. When processing protocol filter configurations, the function fails to adequately validate input parameters or handle edge cases, leading to unauthorized memory access patterns that ultimately result in segmentation faults. This type of vulnerability falls under the CWE-125 vulnerability category, which encompasses out-of-bounds read conditions that can lead to memory corruption and system instability. The flaw demonstrates characteristics consistent with buffer over-read conditions where the function attempts to access memory beyond allocated boundaries, causing the operating system to terminate the process with a segmentation fault signal.
The operational impact of CVE-2019-6136 extends beyond simple application crashes, potentially compromising the stability and reliability of industrial control systems that depend on libIEC61850 for communication protocols. In power grid automation environments where these libraries are extensively deployed, a segmentation fault could lead to service disruption, communication failures between substations, or even cascading failures in critical infrastructure monitoring systems. The vulnerability affects systems implementing IEC 61850 standards, which are fundamental to substation automation systems and smart grid implementations. Attackers could potentially exploit this flaw to cause denial of service conditions, disrupting critical operations in industrial environments where system uptime is paramount for safety and operational continuity.
From an attacker perspective, this vulnerability aligns with ATT&CK technique T1499.004, which covers network disruption attacks through service availability, and represents a potential entry point for more sophisticated attacks targeting industrial control systems. The vulnerability's exploitation requires minimal privileges and can be achieved through the execution of the affected demonstration programs, making it accessible to attackers with basic knowledge of the library's interface. Mitigation strategies should include immediate patching of the libIEC61850 library to version 1.4.0 or later where the issue has been resolved, implementing network segmentation to limit exposure, and conducting thorough security assessments of systems utilizing this library. Organizations should also consider implementing process monitoring and alerting mechanisms to detect potential exploitation attempts and maintain comprehensive incident response procedures for industrial control system environments. The vulnerability underscores the importance of proper input validation and memory management in safety-critical systems where software reliability directly impacts operational safety and infrastructure integrity.