An important-rated security vulnerability in VMware Tools could pave the way for local privilege escalation (LPE) and complete takeover of virtual machines that house important corporate data, user info and credentials, and applications.
VMware Tools is a set of services and modules that enable several features in VMware products used to manage user interactions with guest operating systems (Guest OS). Guest OS is the engine that powers a virtual machine.
“A malicious actor with local non-administrative access to the Guest OS can escalate privileges as a root user in the virtual machine,” according to VMware’s security advisory, issued this week, which noted that the bug, tracked as CVE-2022-31676, carries a rating of 7.0 out of 10 on the CVSS vulnerability-severity scale.
Exploitation paths could take many forms, according to Mike Parkin, senior technical engineer at Vulcan Cyber.
“It is unclear from the release whether it requires access through the VMware virtual console interface or whether a user with some form of remote access to the Guest OS, such as RDP on Windows or shell access for Linux, could exploit the vulnerability,” he tells Dark Reading. “Access to Guest OS should be limited, but there are many use cases that require logging into a virtual machine as a local user.”
The virtualization virtuoso has patched the issue, with patched-version details available in the security alert. There are no workarounds for the flaw, so admins should apply the update to avoid compromise.
The issue, while not critical, should still be patched as soon as practicable, Parkin warns: “Even with cloud migration, VMware remains a staple of virtualization in many enterprise environments, which makes any privilege escalation vulnerability problematic.”
To monitor for compromise, John Bambenek, principal threat hunter at Netenrich, recommends deploying behavioral analytics to detect credential abuse, as well as an insider threat program to detect problem employees who may abuse their already legitimate access.
“VMWare (and related) systems manage the most privileged systems, and compromising them is a force multiplier for threat actors,” he says.
The patch comes on the heels of the disclosure of a critical bug earlier this month that would allow authentication bypass for on-premises VMware implementations, to give attackers initial local access and the ability to exploit LPE vulnerabilities such as this one.
