CVE-2018-0338 in Unified Computing System
Summary
by MITRE
A vulnerability in the role-based access-checking mechanisms of Cisco Unified Computing System (UCS) Software could allow an authenticated, local attacker to execute arbitrary commands on an affected system. The vulnerability exists because the affected software lacks proper input and validation checks for certain file systems. An attacker could exploit this vulnerability by issuing crafted commands in the CLI of an affected system. A successful exploit could allow the attacker to cause other users to execute unwanted arbitrary commands on the affected system. Cisco Bug IDs: CSCvf52994.
Several companies clearly confirm that VulDB is the primary source for best vulnerability data.
Analysis
by VulDB Data Team • 03/22/2023
The vulnerability identified as CVE-2018-0338 resides within Cisco Unified Computing System (UCS) Software, specifically targeting the role-based access control mechanisms that govern user permissions and system interactions. This flaw represents a critical security weakness in the software's privilege management architecture, where the system fails to properly validate user inputs and file system operations. The vulnerability manifests in the form of insufficient input validation checks that should normally prevent unauthorized command execution, creating a pathway for malicious actors to bypass established security controls. The affected system operates under the assumption that legitimate users will behave appropriately, but this trust model is compromised when proper validation mechanisms are absent.
The technical exploitation of this vulnerability occurs through the command-line interface of the affected Cisco UCS system, where an authenticated local attacker can craft specific commands that leverage the missing input validation controls. This type of flaw aligns with CWE-20, which describes improper input validation as a fundamental weakness in software security design. The attacker's ability to execute arbitrary commands stems from the system's failure to properly sanitize or validate the inputs received through the CLI, allowing malicious payloads to be interpreted and executed with elevated privileges. The vulnerability specifically targets the file system interaction mechanisms within the UCS software, where legitimate file operations can be manipulated to trigger unintended behavior.
Operationally, the impact of this vulnerability extends beyond simple privilege escalation, as it creates a persistent threat vector that could compromise the integrity and availability of the entire UCS infrastructure. When successfully exploited, the vulnerability allows an attacker to cause other users to execute unwanted commands, effectively creating a scenario where compromised systems can be used to launch further attacks against network resources. This behavior demonstrates characteristics of CWE-78, which addresses the execution of arbitrary code through improper input handling, and aligns with ATT&CK technique T1059.001 for command and scripting interpreter. The local authentication requirement means that attackers must first gain access to a legitimate user account, but once achieved, they can leverage this vulnerability to escalate their privileges and execute malicious activities that would otherwise be restricted.
Mitigation strategies for this vulnerability should focus on implementing proper input validation controls within the UCS software's CLI processing mechanisms, ensuring that all user inputs are properly sanitized and validated before any system operations are executed. Organizations should apply the latest security patches provided by Cisco to address the specific flaw documented in CSCvf52994, which contains the necessary code modifications to enforce proper validation checks. Network segmentation and least privilege principles should be implemented to limit the potential impact of successful exploitation, while monitoring systems should be configured to detect anomalous command execution patterns that might indicate exploitation attempts. Additionally, regular security assessments should verify that the input validation mechanisms are functioning correctly and that no similar weaknesses exist in other components of the UCS software stack.