CVE-2026-18263: Parallels RAS Client RDP Backend Service Exposed Dangerous Function Local Privilege Escalation Vulnerability
Parallels RAS Client RDP Backend Service Exposed Dangerous Function Local Privilege Escalation Vulnerability. This vulnerability allows local attackers to escalate privileges on affected installations of Parallels RAS Client. An attacker must first obtain the ability to execute low-privileged code on the target system in order to exploit this vulnerability.
The specific flaw exists within the RAS RDP Backend Service. The issue results from an exposed dangerous function. An attacker can leverage this vulnerability to escalate privileges and execute arbitrary code in the context of SYSTEM. Was ZDI-CAN-28886.
Affected Software
Remediation
Recommended actions to resolve this vulnerability, in priority order.
- Compensating control
Mitigate local privilege escalation risk by restricting local access to the Parallels RAS Client system/service that hosts the "RAS RDP Backend Service" (e.g., limit who can execute low-privileged code on the host).
- Compensating control
Apply compensating isolation controls to prevent untrusted local users from reaching the Parallels RAS Client RDP backend component (e.g., isolate/lock down the environment to trusted accounts only).
Event History
Frequently Asked Questions
What level of access does an attacker need before exploiting this issue?
The attacker must already be able to execute code on the target system with low privileges. The vulnerability is therefore a local privilege-escalation issue rather than an initial-access mechanism.
What is the impact after successful exploitation?
An attacker can escalate privileges and execute arbitrary code in the context of SYSTEM, giving them full control of the affected Windows system.