ZDI-CAN-28886: ZDI-26-556: 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.
Other sources
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 ZDI has assigned a CVSS rating of 7.8. The following CVEs are assigned: CVE-2026-18263.
— ZDI
Affected Software
Remediation
Recommended actions to resolve this vulnerability, in priority order.
- Upgrade
Upgrade
Parallels RAS Clientto a version that resolves this vulnerability.Patch ZDI-26-556 - Compensating control
Mitigate exploitation of the exposed dangerous function in the Parallels RAS Client RDP Backend Service by restricting access/interaction with the RAS Client RDP Backend Service so that only authorized users/processes can reach it (e.g., network/firewall/ACL limitations around the RDP Backend Service).
Event History
Frequently Asked Questions
What is the severity of ZDI-CAN-28886?
The severity of ZDI-CAN-28886 is rated at 7.8 on the CVSS scale.
How do I fix ZDI-CAN-28886?
To mitigate ZDI-CAN-28886, update your Parallels RAS Client to the latest version provided by the vendor.
Who is affected by ZDI-CAN-28886?
ZDI-CAN-28886 affects installations of the Parallels RAS Client where local attackers can execute low-privileged code.
Can ZDI-CAN-28886 be exploited remotely?
No, ZDI-CAN-28886 requires local access to the affected system for exploitation.
What type of vulnerability is ZDI-CAN-28886?
ZDI-CAN-28886 is a local privilege escalation vulnerability.