CVE-2018-8838 in CENTUM CS 1000
Summary
by MITRE
A weakness in access controls in CENTUM CS 1000 all versions, CENTUM CS 3000 versions R3.09.50 and earlier, CENTUM CS 3000 Small versions R3.09.50 and earlier, CENTUM VP versions R6.03.10 and earlier, CENTUM VP Small versions R6.03.10 and earlier, CENTUM VP Basic versions R6.03.10 and earlier, Exaopc versions R3.75.00 and earlier, B/M9000 CS all versions, and B/M9000 VP versions R8.01.01 and earlier may allow a local attacker to exploit the message management function of the system. A CVSS v3 base score of 6.5 has been calculated; the CVSS vector string is (AV:L/AC:H/PR:L/UI:N/S:U/C:L/I:H/A:H).
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Analysis
by VulDB Data Team • 01/25/2020
The vulnerability described in CVE-2018-8838 represents a critical access control weakness affecting multiple industrial control system platforms including CENTUM CS 1000, CENTUM CS 3000, CENTUM VP, and Exaopc systems. This flaw resides within the message management function of these systems, which serves as a fundamental component for communication and data handling within industrial environments. The vulnerability specifically targets local attackers who can exploit the insufficient access controls to gain unauthorized privileges and potentially compromise the entire control system infrastructure. The CVSS v3 base score of 6.5 indicates a medium to high severity threat that requires immediate attention from system administrators and security teams responsible for industrial control systems.
The technical implementation of this vulnerability stems from inadequate authentication and authorization mechanisms within the message management subsystem. Attackers with local access to the system can exploit this weakness to manipulate system messages and potentially escalate their privileges from a local user to a higher privilege level. This represents a classic privilege escalation vulnerability where the system fails to properly validate access rights when processing messages. The attack vector is classified as local (AV:L) meaning an attacker must already have access to the system, but the attack complexity is high (AC:H) due to the specific nature of the exploitation required. The vulnerability affects a broad range of industrial control systems and is particularly concerning due to the critical nature of these environments where system integrity and availability are paramount.
The operational impact of this vulnerability extends beyond simple unauthorized access as it can lead to significant disruptions in industrial processes and potential safety hazards. When an attacker successfully exploits this vulnerability, they can modify system messages, potentially causing incorrect control actions that could result in equipment damage, production losses, or even safety incidents. The compromise of message management functions directly impacts the integrity and availability of the control system, as malicious actors could manipulate communication between system components. The CVSS scoring indicates that this vulnerability can cause high impact to both integrity (I:H) and availability (A:H) while also potentially exposing confidential information (C:L). This makes the vulnerability particularly dangerous in environments where industrial control systems manage critical infrastructure such as power generation, water treatment, or manufacturing processes.
Organizations affected by this vulnerability should implement immediate mitigations including applying available vendor patches and updates to bring systems up to supported versions. Network segmentation and access control measures should be enhanced to limit local access to critical systems, while monitoring should be implemented to detect unusual message handling activities. The vulnerability aligns with CWE-284 which describes improper access control in software systems, and could potentially be leveraged as part of broader attack chains that follow ATT&CK framework tactics such as privilege escalation and persistence. System administrators should conduct thorough vulnerability assessments across their industrial control environments and consider implementing additional security controls like mandatory access controls and enhanced logging to detect potential exploitation attempts. Regular security audits and penetration testing should be performed to ensure that access controls remain effective against evolving threats in industrial environments.