CVE-2021-37720 in SD-WAN Software and Gateways
Summary
by MITRE • 09/07/2021
A remote arbitrary command execution vulnerability was discovered in Aruba SD-WAN Software and Gateways; Aruba Operating System Software version(s): Prior to 8.6.0.4-2.2.0.4; Prior to 8.7.1.4, 8.6.0.9, 8.5.0.13, 8.3.0.16, 6.5.4.20, 6.4.4.25. Aruba has released patches for Aruba SD-WAN Software and Gateways and ArubaOS that address this security vulnerability.
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Analysis
by VulDB Data Team • 09/10/2021
The vulnerability identified as CVE-2021-37720 represents a critical remote arbitrary command execution flaw affecting Aruba SD-WAN Software and Gateways operating on ArubaOS. This security weakness allows attackers to execute malicious commands on affected systems without requiring authentication, making it particularly dangerous for network infrastructure deployments. The vulnerability impacts multiple software versions across different release lines including 8.6.0.4, 8.7.1.4, 8.6.0.9, 8.5.0.13, 8.3.0.16, 6.5.4.20, and 6.4.4.25, indicating a widespread issue affecting legacy and current system deployments. The flaw resides in the command processing mechanisms of the ArubaOS software, specifically in how the system handles input validation for administrative commands, creating an attack surface that can be exploited remotely.
The technical implementation of this vulnerability stems from insufficient input sanitization and validation within the ArubaOS command execution framework. Attackers can craft malicious payloads that bypass authentication mechanisms and directly invoke system commands through vulnerable interfaces. This type of vulnerability aligns with CWE-77 and CWE-78 classifications, representing command injection flaws that enable unauthorized code execution. The root cause typically involves improper handling of user-supplied data in command construction, where input parameters are directly concatenated into system calls without adequate sanitization or escaping mechanisms. The vulnerability's remote nature means that attackers can exploit it from external network positions without requiring physical access or legitimate credentials, making it particularly attractive for automated exploitation campaigns.
The operational impact of CVE-2021-37720 extends beyond simple unauthorized command execution, creating significant risks for network security and business continuity. Organizations utilizing affected Aruba SD-WAN solutions face potential complete system compromise, data exfiltration, and disruption of critical network services. The vulnerability can be leveraged to establish persistent backdoors, modify network configurations, and potentially pivot to other systems within the network perimeter. Given that SD-WAN gateways serve as critical network infrastructure components, successful exploitation could result in complete network disruption, unauthorized access to sensitive data flows, and potential compromise of the entire enterprise network infrastructure. The attack surface is particularly concerning as these devices often serve as central points for network traffic management and security policy enforcement.
Mitigation strategies for CVE-2021-37720 primarily focus on immediate software patching and configuration hardening. Organizations should prioritize upgrading to ArubaOS versions 8.6.0.4-2.2.0.4, 8.7.1.4, 8.6.0.9, 8.5.0.13, 8.3.0.16, 6.5.4.20, and 6.4.4.25 or later releases that contain the vendor-provided security patches. Network segmentation and access control measures should be implemented to limit exposure of affected devices to untrusted networks. Additional protective measures include monitoring for suspicious command execution patterns, implementing network intrusion detection systems, and conducting comprehensive vulnerability assessments of the affected network infrastructure. The ATT&CK framework categorizes this vulnerability under T1059.001 for command and scripting interpreter and T1068 for exploit for privilege escalation, highlighting the need for comprehensive defensive strategies that address both initial compromise and lateral movement capabilities. Organizations should also consider implementing zero trust network architectures that minimize the impact of such vulnerabilities by reducing the attack surface and enforcing strict access controls.