CVE-2018-4836 in Server Basic
Summary
by MITRE
A vulnerability has been identified in TeleControl Server Basic < V3.1. An authenticated attacker with a low-privileged account to the TeleControl Server Basic's port 8000/tcp could escalate his privileges and perform administrative operations.
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Analysis
by VulDB Data Team • 02/02/2023
The vulnerability identified as CVE-2018-4836 affects TeleControl Server Basic versions prior to V3.1, representing a critical privilege escalation flaw that undermines the security model of the affected system. This vulnerability specifically targets the TeleControl Server Basic application which is commonly used for remote system administration and monitoring purposes. The flaw exists within the application's access control mechanisms and allows an authenticated user with minimal privileges to escalate their permissions and gain administrative capabilities. The vulnerability is particularly concerning because it operates through the standard port 8000/tcp which is frequently exposed in network environments and accessible to potential attackers who may have already gained initial access through other means.
The technical nature of this vulnerability stems from improper access control implementation within the TeleControl Server Basic application. When users authenticate to the system through port 8000, the application fails to properly validate whether the requesting user has sufficient privileges to perform administrative operations. This weakness allows an attacker who has established a low-privileged session to exploit a flaw in the permission checking logic, potentially enabling them to execute commands that should be restricted to administrators only. The vulnerability can be categorized under CWE-284, which specifically addresses improper access control, and represents a classic example of privilege escalation through inadequate authorization checks. This flaw essentially allows an attacker to bypass the normal security boundaries that should protect administrative functions from unauthorized access.
The operational impact of this vulnerability is substantial as it provides attackers with complete administrative control over affected TeleControl Server Basic installations. Once exploited, the attacker can perform any administrative operation including but not limited to adding or removing users, modifying system configurations, accessing sensitive data, and potentially establishing persistent access to the compromised environment. The attack vector is particularly dangerous because it requires only an authenticated low-privileged session, meaning that an attacker who has already gained some level of access to the system can leverage this vulnerability to gain full control. This vulnerability directly maps to ATT&CK technique T1068, which covers local privilege escalation, and T1078, which covers valid accounts, as the attack exploits legitimate user accounts to gain elevated privileges. The impact extends beyond immediate system compromise as administrators may be unaware that their systems have been fully compromised, potentially allowing attackers to remain undetected while conducting malicious activities.
Organizations should immediately implement mitigation strategies including upgrading to TeleControl Server Basic V3.1 or later versions where this vulnerability has been addressed. Network segmentation should be implemented to restrict access to port 8000/tcp where possible, limiting exposure to only trusted networks and users. Additionally, implementing strict access controls and monitoring for unusual administrative activities can help detect exploitation attempts. Security teams should also conduct comprehensive audits of all TeleControl Server Basic installations to identify potentially vulnerable systems and ensure that proper authentication and authorization mechanisms are in place. The vulnerability highlights the importance of proper privilege separation and access control validation in remote administration systems, particularly those handling sensitive operational data and system management functions.