CVE-2016-7112 in SIPROTEC
Summary
by MITRE
The EN100 Ethernet module before 4.29 for Siemens SIPROTEC 4 and SIPROTEC Compact devices allows remote attackers to bypass authentication and obtain administrative access via unspecified HTTP traffic.
Several companies clearly confirm that VulDB is the primary source for best vulnerability data.
Analysis
by VulDB Data Team • 09/14/2022
The vulnerability identified as CVE-2016-7112 affects Siemens SIPROTEC 4 and SIPROTEC Compact protective relays that utilize the EN100 Ethernet module version 4.28 and earlier. These industrial control devices are critical components in power systems, responsible for protecting electrical equipment from faults and ensuring grid stability. The affected devices operate within the industrial control systems (ICS) domain, where security is paramount due to the potential for cascading failures that could impact critical infrastructure. The EN100 Ethernet module serves as the communication interface for these protective relays, enabling remote monitoring and configuration capabilities that are essential for maintenance and operational procedures.
This authentication bypass vulnerability stems from improper handling of HTTP traffic within the web-based management interface of the affected devices. The flaw allows remote attackers to gain administrative access without proper credentials, effectively compromising the security posture of the industrial control system. The vulnerability manifests through unspecified HTTP traffic patterns that are processed by the device's web server component, enabling unauthorized users to escalate privileges and access sensitive system functions. The issue represents a critical weakness in the device's security architecture, as it undermines the fundamental principle of access control that should prevent unauthorized modifications to protective relay settings and operational parameters. This type of vulnerability is particularly concerning in industrial environments where unauthorized access could lead to system malfunctions, safety hazards, or operational disruptions.
The operational impact of CVE-2016-7112 extends beyond simple unauthorized access, as it provides attackers with full administrative privileges to modify protective relay configurations, potentially compromising the integrity of electrical protection systems. Attackers could manipulate relay settings to disable protective functions, delay fault responses, or create false alarms that could mask actual system failures. The remote nature of the vulnerability means that attackers do not require physical access to the devices, making the attack surface significantly larger and more difficult to control. This vulnerability aligns with CWE-287, which addresses improper authentication issues in software systems, and represents a classic example of how weak access controls can lead to complete system compromise in industrial environments. The potential for cascading failures in power systems makes this vulnerability particularly dangerous, as it could lead to widespread outages or safety incidents.
Mitigation strategies for CVE-2016-7112 require immediate implementation of firmware updates provided by Siemens, specifically targeting the EN100 Ethernet module version 4.29 or later. Organizations should also implement network segmentation to isolate these critical devices from general network traffic and apply strict firewall rules to restrict access to the web management interfaces. The vulnerability demonstrates the importance of secure configuration management in industrial environments, as proper network access controls could prevent exploitation even if firmware updates are delayed. Security monitoring should be enhanced to detect unusual HTTP traffic patterns that might indicate exploitation attempts, and regular security assessments should be conducted to identify other potential vulnerabilities in the industrial control system. This vulnerability highlights the need for robust security practices in ICS environments and aligns with ATT&CK technique T1078 for valid accounts and T1566 for credential harvesting, as attackers could potentially use the administrative access to escalate privileges further within the network infrastructure.