ZDI-26-554: 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-2026-13121.
— 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-26-554 - Compensating control
Mitigate by reducing exposure of the RAS RDP Backend Service’s exposed dangerous function to untrusted/local low-privileged code paths (e.g., restrict access to the service/components that permit low-privileged execution).
Event History
Frequently Asked Questions
What is the severity of ZDI-26-554?
The severity of ZDI-26-554 is rated at 7.8 according to the CVSS scoring system.
How do I fix ZDI-26-554?
To fix ZDI-26-554, update your Parallels RAS Client to the latest version available from the official source.
Who is affected by ZDI-26-554?
ZDI-26-554 affects installations of Parallels RAS Client where local attackers can exploit this privilege escalation vulnerability.
What type of vulnerability is ZDI-26-554?
ZDI-26-554 is a local privilege escalation vulnerability found in the RDP Backend Service of Parallels RAS Client.
What are the exploit requirements for ZDI-26-554?
To exploit ZDI-26-554, an attacker must first run low-privileged code on the target system.