CVE-2012-4096 in Unified Computing System
Summary
by MITRE
The local file editor in the Baseboard Management Controller (BMC) in Cisco Unified Computing System (UCS) allows local users to gain privileges and modify arbitrary fabric-interconnect files, in the context of a vi process, via unspecified commands, aka Bug ID CSCtn06574.
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Analysis
by VulDB Data Team • 03/01/2019
The vulnerability identified as CVE-2012-4096 represents a critical privilege escalation flaw within the Baseboard Management Controller (BMC) of Cisco Unified Computing System (UCS) infrastructure. This vulnerability specifically affects the local file editor functionality that operates within the vi process context, creating a significant security risk for enterprise data center environments. The BMC serves as a critical management component for UCS systems, providing out-of-band management capabilities and serving as a gateway for administrative operations. When local users can exploit this vulnerability, they gain unauthorized access to modify critical fabric-interconnect files that control network connectivity and system behavior.
The technical nature of this vulnerability stems from insufficient input validation and privilege separation mechanisms within the BMC's file editing interface. The unspecified commands that trigger this flaw likely involve manipulation of file paths, access permissions, or process execution contexts that allow local attackers to escalate their privileges beyond normal user boundaries. The vi process context is particularly concerning because vi is a powerful text editor that typically operates with elevated privileges when managing system configuration files. This vulnerability falls under CWE-264, which addresses permissions, privileges, and access controls, specifically focusing on inadequate privilege separation and insufficient access control mechanisms.
The operational impact of CVE-2012-4096 extends far beyond simple file modification capabilities, as fabric-interconnect files control critical network infrastructure within UCS environments. An attacker who successfully exploits this vulnerability can potentially disrupt network connectivity, modify system configurations, or establish persistent access points within the data center infrastructure. The implications are particularly severe because UCS systems typically serve as core components of enterprise data center architectures, making this vulnerability a prime target for attackers seeking to compromise large-scale network environments. This flaw directly aligns with ATT&CK technique T1068, which covers "Exploitation for Privilege Escalation," and T1566, covering "Phishing for Information," as local privilege escalation often serves as a foundation for broader attacks.
Organizations affected by this vulnerability should implement immediate mitigations including restricting local access to BMC interfaces, implementing strict access controls for the vi process, and conducting comprehensive audits of fabric-interconnect file permissions. System administrators should also consider disabling unnecessary local file editing capabilities and ensuring proper privilege separation between user and administrative processes. The vulnerability demonstrates the critical importance of secure configuration management in enterprise infrastructure, as it highlights how seemingly minor flaws in local management interfaces can provide attackers with significant leverage. Regular security assessments and vulnerability scanning should be implemented to identify similar privilege escalation vulnerabilities across the entire UCS infrastructure. Additionally, organizations should maintain up-to-date firmware and security patches from Cisco to address this and related vulnerabilities that could compromise their data center security posture.