IT administrators often face pressure to give users more control over their virtual desktops and remote sessions. Granting local administrator privileges in Virtual Desktop Infrastructure (VDI) or Remote Desktop Session Host (RDSH) environments might seem like a convenient shortcut to reduce support calls – after all, power users could install their own software or troubleshoot issues without IT intervention. However, this convenience comes at a steep cost. In practice, allowing standard users to have local admin rights on shared or virtualized systems is a ticking time bomb that can undermine both security and stability. Studies have shown that a vast majority of critical Windows vulnerabilities can be mitigated simply by removing admin rights (beyondtrust.com). In other words, handing out local admin access is like leaving the keys under the welcome mat – it dramatically widens the attack surface and exposes your entire network to potential compromise. This article explores the key security and operational risks of this practice, and why “letting users be admins” in VDI/RDSH is a recipe for disaster.
Security Risks: Privilege Escalation and Network Compromise
Attacker’s “privileged pathway” in a Windows network: Even a single local admin account breach can let an attacker escalate step-by-step from an initial foothold to complete domain takeover. In this illustrated scenario, a phishing email leads to malware on a user’s machine, which then uses that user’s local admin rights to disable security tools and harvest credentials. The attacker moves laterally to other hosts and eventually compromises a domain controller – gaining “keys to the kingdom” control over the entire environment(cyberark.com). It only takes one user with admin rights for an intruder to leapfrog through your network in this way.
When a user running in a VDI or RDSH session has local admin privileges, an attacker who hijacks that session essentially gains the same power as an IT administrator on that machine. No matter how strong your perimeter defenses are, a local admin account can bypass or disable security controls and operate with impunity(reddit.com). For example, during a penetration test, security consultants demonstrated that compromising a single user account with local admin rights allowed them to do all of the following:
Disable security software – e.g. turning off endpoint antivirus and firewalls, leaving the system defenseless.
Install malicious programs – malware, keyloggers, or backdoors can be added and run at will, often without triggering alerts.
Encrypt or destroy data – running ransomware becomes trivial when the user can encrypt files or delete backups.
Move laterally within the network – the compromised admin account can connect to other computers or servers, looking for further access.
Cover tracks and persist – critical event logs can be wiped and system settings modified to help the attacker avoid detection and maintain access.
Such capabilities effectively let a hacker weaponize that virtual desktop or session host against the organization. In one real-world test, a stolen user account with local admin rights even had administrative access to a company’s primary domain controller – giving the attackers unrestricted control over all domain resources. This illustrates how a seemingly isolated VDI VM or RDSH server, once breached, can serve as a launchpad to compromise the broader network.
Local admin privileges also make privilege escalation attacks far easier. Windows caches credentials and hashes in memory, and admin rights let attackers extract those secrets with tools like Mimikatz. If all your VDI instances share the same local administrator password (a common setup when using a standard gold image), an attacker who cracks or “passes” that hash can immediately pivot into other machines across the environment(securden.com). From there, they can hunt for higher-value accounts. It’s not uncommon that an RDSH or VDI host might have had a domain admin log on at some point; an intruder with local admin access can dump those domain admin hashes as well. In an Active Directory domain, this turns a single compromised desktop into a full domain compromise nightmare.
The multi-user nature of RDSH adds another layer of risk: a local administrator on a session host can potentially spy on or interfere with other users’ sessions on that same server. Admin-level malware could capture keystrokes or screen data from other logged-in users, or even impersonate their accounts. Essentially, the isolation between user sessions breaks down once someone has admin control of the underlying OS. Between the ability to impersonate users, disable protections, and spread laterally, a malicious actor with local admin rights can quickly escalate a minor intrusion into a major breach(security.stackexchange.com).
Security Bottom Line: Granting local admin access in VDI/RDSH removes critical security barriers. It provides attackers a stable foothold with elevated privileges, letting them persist on the host, evade detection, harvest credentials, and traverse the network at will. This amplifies the impact of any malware or breach exponentially – turning what could have been a contained incident into an organization-wide compromise.
Operational Risks: Instability and Management Nightmares
Security threats aren’t the only concern – giving users free rein as local administrators can also wreak havoc on the stability and manageability of your VDI/RDSH environment. These platforms are typically designed for consistency and control. When users run as admins, that discipline goes out the window, leading to a host of operational problems.
Unpredictable system changes become a daily headache. Users with admin rights can install or remove software, drivers, and updates at will, which might conflict with standardized configurations. In a pooled VDI scenario, those changes might be temporary, but in persistent virtual desktops (or on an RDSH server), one user’s tinkering can easily break applications or degrade performance for everyone. For instance, an uninformed user might unintentionally uninstall a critical system component or service, causing application failures. In an RDSH environment, such an action could bring down the entire host or destabilize it for dozens of other users in that session farm. The result is unscheduled downtime and frantic firefighting for IT.
Allowing local admins also leads to configuration drift and “one-off” issues that make support much more difficult. Instead of a uniform baseline to manage, IT now has to deal with VMs or servers that each might be unique “snowflakes” due to user modifications. Troubleshooting becomes a guessing game of what the user might have changed this time. It’s no surprise that organizations see a spike in helpdesk tickets when users have administrator rights – everything from misconfigured network settings to malware infections end up in IT’s queue. In contrast, companies that revoked local admin access reported a sharp drop in support incidents (one anecdotal report noted ~90% fewer tickets) once users could no longer “break” their machines so easily.
There are also compliance and licensing risks. Users with admin rights can install unapproved or pirated software, store data insecurely, or otherwise violate company policies and regulatory requirements without oversight. IT loses control over what is running in the environment, which can lead to audit findings or legal liabilities. As one security expert bluntly noted, giving end users admin privileges “needlessly complicates your environment” and even introduces legal/regulatory risks through things like unlicensed software and uncontrolled applications. In highly regulated sectors, the inability to enforce standard configurations and software inventories can itself be a serious issue.
Finally, consider resilience and recovery. A user with admin rights can disable backups, delete system logs, or even create backdoor accounts. This not only helps attackers hide, but it also means that if something goes wrong (whether malicious or accidental) the normal safety nets might be gone. Restoring a messed-up VDI image or rebuilding a compromised RDSH server on the fly is not a trivial task, especially during a security incident. The operational disruption and workload on IT teams can be immense.
Operations Bottom Line: Local admin rights turn a well-managed VDI/RDSH deployment into a Wild West of unpredictable changes and potential chaos. The environment becomes harder to support and prone to outages, as users can inadvertently undermine system stability. You’ll spend significantly more time fixing broken VMs/servers and cleaning up after unauthorized changes – all while possibly falling out of compliance in the process.
Conclusion
In VDI and RDSH contexts, the risks far outweigh the convenience of granting users local administrator privileges. What might save a few minutes on a support call can open the door to massive security breaches and operational headaches. A user with admin rights can unwittingly (or deliberately) punch holes in your defenses and destabilize critical systems. The lesson for IT administrators is clear: least privilege is not just a motto, but a necessity in multi-user and virtual desktop environments. By keeping users out of the local administrators group, you preserve the integrity, security, and reliability of the entire infrastructure. In the end, resisting the urge to grant those rights will save your organization from countless dangers – proving that a locked-down environment is much safer and easier to manage than one where every user holds the keys to the kingdom.
Sources: The insights above are based on industry reports, security blogs, and expert commentary on the impacts of local admin access in enterprise environments. For example, BeyondTrust’s analysis of Microsoft vulnerabilities highlights how removing admin rights mitigates over 90% of critical Windows flaws. Cybersecurity firms and professionals (SBS CyberSecurity, CyberArk, and others) have documented how attackers exploit admin-level access to disable protections, harvest credentials, and traverse networks. Real-world pen tests and admin experiences further illustrate the resulting operational turmoil – from rogue software installations to surges in support tickets. The consensus is universal: in VDI/RDSH settings, no user should be casually given local admin privileges(cyberark.com). The cost to security and stability is simply too high.
