CVE-2019-1664 in HyperFlex Software
Summary
by MITRE
A vulnerability in the hxterm service of Cisco HyperFlex Software could allow an unauthenticated, local attacker to gain root access to all nodes in the cluster. The vulnerability is due to insufficient authentication controls. An attacker could exploit this vulnerability by connecting to the hxterm service as a non-privileged, local user. A successful exploit could allow the attacker to gain root access to all member nodes of the HyperFlex cluster. This vulnerability affects Cisco HyperFlex Software Releases prior to 3.5(2a).
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Analysis
by VulDB Data Team • 05/11/2020
The vulnerability identified as CVE-2019-1664 represents a critical security flaw within Cisco HyperFlex Software that undermines the fundamental integrity of distributed computing environments. This issue resides within the hxterm service component, which serves as a terminal access mechanism for HyperFlex cluster management. The vulnerability manifests as a severe authentication bypass that allows unauthenticated local attackers to escalate privileges to root access across all nodes within a HyperFlex cluster. The flaw specifically targets the insufficient authentication controls implemented within the service, creating an exploitable pathway that bypasses normal security boundaries. This vulnerability affects Cisco HyperFlex Software releases prior to version 3.5(2a), indicating that organizations running older software versions remain at significant risk of compromise.
The technical exploitation of this vulnerability follows a predictable attack pattern where a local user with minimal privileges can connect to the hxterm service and leverage the authentication weakness to gain root access. This privilege escalation occurs without requiring any authentication credentials, making the attack vector particularly dangerous as it requires no network connectivity or external attack surfaces. The attacker need only establish a local connection to the service and execute specific commands that trigger the authentication bypass mechanism. This flaw essentially creates a backdoor within the system's privilege management framework, allowing unauthorized users to assume complete administrative control over cluster nodes. The vulnerability's impact extends beyond individual nodes to encompass the entire cluster infrastructure, as root access on one node typically provides access to the broader distributed system.
The operational impact of CVE-2019-1664 is devastating for organizations relying on Cisco HyperFlex environments, as it enables complete system compromise without requiring external network access or sophisticated attack techniques. Once exploited, attackers can manipulate cluster configurations, access sensitive data, modify system parameters, and potentially disrupt critical business operations. The vulnerability's location within the hxterm service means that even organizations with robust network security measures may be compromised if an attacker gains local access to any cluster node. This represents a significant risk in environments where physical access controls are inadequate or where insider threats exist. The vulnerability also affects the integrity of the entire HyperFlex platform, as root access allows attackers to modify system binaries, disable security features, or establish persistent access mechanisms. Organizations may face regulatory compliance violations and significant financial losses due to data breaches or service disruptions caused by this vulnerability.
Organizations should implement immediate mitigation strategies to address this vulnerability, including upgrading to Cisco HyperFlex Software version 3.5(2a) or later to receive the necessary security patches. Network segmentation and access control measures should be strengthened to limit local access to cluster nodes, while monitoring systems should be deployed to detect unauthorized connections to the hxterm service. The vulnerability aligns with CWE-287, which addresses improper authentication issues, and represents a clear violation of the principle of least privilege. From an ATT&CK framework perspective, this vulnerability maps to privilege escalation techniques and local persistence mechanisms, making it particularly dangerous in environments where attackers may already have limited access. Regular security assessments and vulnerability scanning should be conducted to identify systems running affected software versions, while incident response procedures should be updated to address potential exploitation of this specific vulnerability. The remediation process requires careful planning to ensure that upgrades do not disrupt existing cluster operations, and organizations should validate that the patch properly addresses the authentication bypass mechanism before deployment.