ZDI-26-555: 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 ZDI has assigned a CVSS rating of 7.8. The following CVEs are assigned: CVE-2026-18262.
AI Analysis
Technical Summary
CVE-2026-18262 is a local privilege escalation vulnerability in the Parallels RAS Client RDP Backend Service caused by an exposed dangerous function. Exploitation requires prior ability to run low-privileged code on the affected system. Successful exploitation allows an attacker to escalate privileges to SYSTEM and execute arbitrary code with high impact on confidentiality, integrity, and availability. The vulnerability was responsibly disclosed to Parallels on 2026-02-25 and publicly released on 2026-08-11. The vendor fixed the issue in Parallels RAS Client version 21.2.
Potential Impact
An attacker who can execute low-privileged code locally on a system running a vulnerable version of Parallels RAS Client can escalate their privileges to SYSTEM level. This grants full control over the affected system, allowing arbitrary code execution with the highest privileges, which can compromise confidentiality, integrity, and availability of the system.
Mitigation Recommendations
Upgrade Parallels RAS Client to version 21.2 or later, where this vulnerability has been fixed. No other mitigation or workaround is indicated by the vendor advisory.
ZDI-26-555: Parallels RAS Client RDP Backend Service Exposed Dangerous Function Local Privilege Escalation Vulnerability
Description
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-2026-18262.
Affected software
pkg:github/parallels/ras-clientRun on your own infrastructure? Check whether these packages are installed with threat-finder — our free open-source scanner.
AI-Powered Analysis
Machine-generated threat intelligence
Technical Analysis
CVE-2026-18262 is a local privilege escalation vulnerability in the Parallels RAS Client RDP Backend Service caused by an exposed dangerous function. Exploitation requires prior ability to run low-privileged code on the affected system. Successful exploitation allows an attacker to escalate privileges to SYSTEM and execute arbitrary code with high impact on confidentiality, integrity, and availability. The vulnerability was responsibly disclosed to Parallels on 2026-02-25 and publicly released on 2026-08-11. The vendor fixed the issue in Parallels RAS Client version 21.2.
Potential Impact
An attacker who can execute low-privileged code locally on a system running a vulnerable version of Parallels RAS Client can escalate their privileges to SYSTEM level. This grants full control over the affected system, allowing arbitrary code execution with the highest privileges, which can compromise confidentiality, integrity, and availability of the system.
Mitigation Recommendations
Upgrade Parallels RAS Client to version 21.2 or later, where this vulnerability has been fixed. No other mitigation or workaround is indicated by the vendor advisory.
Technical Details
- Classification
- {"confidence":0.95,"severitySource":"cvss-text","classifier":"rss-v2"}
- Article Source
- {"url":"http://www.zerodayinitiative.com/advisories/ZDI-26-555/","fetched":true,"fetchedAt":"2026-08-12T20:03:24.968Z","wordCount":186}
Threat ID: 6a7cd317bf8831d5391487c8
Added to database: 08/12/2026, 20:09:59 UTC
Last enriched: 08/12/2026, 20:12:00 UTC
Last updated: 08/12/2026, 22:41:02 UTC
Views: 3
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