CVE-2022-20921 in ACI Multi-Site Orchestrator
Summary
by MITRE • 08/25/2022
A vulnerability in the API implementation of Cisco ACI Multi-Site Orchestrator (MSO) could allow an authenticated, remote attacker to elevate privileges on an affected device. This vulnerability is due to improper authorization on specific APIs. An attacker could exploit this vulnerability by sending crafted HTTP requests. A successful exploit could allow an attacker who is authenticated with non-Administrator privileges to elevate to Administrator privileges on an affected device.
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Analysis
by VulDB Data Team • 10/02/2022
The vulnerability identified as CVE-2022-20921 represents a critical authorization flaw within Cisco ACI Multi-Site Orchestrator implementation that fundamentally undermines the security posture of network infrastructure management systems. This vulnerability specifically targets the API layer of the MSO platform, which serves as the central orchestration point for managing Cisco ACI fabric deployments across multiple sites. The affected system operates within enterprise data centers where network configuration and policy enforcement are critical for maintaining security boundaries and operational integrity.
The technical root cause of this vulnerability stems from inadequate authorization controls implemented within specific API endpoints that should require administrative privileges for access. This flaw manifests as a failure in the access control mechanisms that should enforce privilege separation between regular user accounts and administrative functions. The improper authorization implementation allows authenticated users to manipulate HTTP request parameters in ways that bypass normal security checks, effectively enabling privilege escalation from standard user accounts to full administrative privileges. This type of vulnerability aligns with CWE-285, which specifically addresses improper authorization issues in software implementations.
The operational impact of this vulnerability extends far beyond simple privilege escalation, as it provides attackers with complete control over the Multi-Site Orchestrator's management functions. Once successfully exploited, an attacker gains the ability to modify network policies, configure routing and switching rules, manage user accounts, and potentially access sensitive network data. The implications are particularly severe in enterprise environments where the MSO orchestrator serves as the central point for managing complex multi-site network deployments, potentially allowing attackers to compromise the entire network infrastructure under management. This vulnerability directly maps to ATT&CK technique T1078.004, which covers valid accounts with elevated privileges, and T1548.001, covering abuse of group privileges.
The exploitation vector requires an authenticated attacker who already possesses valid credentials, but this requirement does not mitigate the severity of the vulnerability. The attack surface is particularly concerning because network administrators often maintain multiple accounts with varying privilege levels, and a single compromised account could provide access to this escalation path. Organizations running Cisco ACI Multi-Site Orchestrator deployments should consider implementing immediate mitigations including network segmentation of management interfaces, enhanced monitoring of API access patterns, and regular privilege reviews. The vulnerability highlights the importance of principle of least privilege enforcement and demonstrates the critical need for comprehensive access control testing in network management systems. Additionally, organizations should consider implementing additional authentication controls such as multi-factor authentication for administrative accounts and regular security assessments of API implementations to prevent similar authorization bypass vulnerabilities from being exploited in the future.