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 ZDI has assigned a CVSS rating of 7.8. The following CVEs are assigned: CVE-2026-13121.
AI Analysis
Technical Summary
CVE-2026-13121 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 execute low-privileged code on the target system. Successful exploitation allows an attacker to escalate privileges to SYSTEM level and execute arbitrary code. The vulnerability has a CVSS v3 base score of 7.8 (AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H). The vendor fixed the issue in version 21.2 of Parallels RAS Client.
Potential Impact
An attacker who can run low-privileged code locally on a system with the vulnerable Parallels RAS Client can escalate their privileges to SYSTEM level. This allows full control over the affected system, including the ability to execute arbitrary code with the highest privileges, potentially compromising confidentiality, integrity, and availability.
Mitigation Recommendations
Apply the official patch by upgrading to Parallels RAS Client version 21.2 or later, where this vulnerability is fixed. Until patched, restrict local code execution capabilities to trusted users only to reduce risk.
ZDI-26-554: 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-2026-13121.
Affected software
AI-Powered Analysis
Machine-generated threat intelligence
Technical Analysis
CVE-2026-13121 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 execute low-privileged code on the target system. Successful exploitation allows an attacker to escalate privileges to SYSTEM level and execute arbitrary code. The vulnerability has a CVSS v3 base score of 7.8 (AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H). The vendor fixed the issue in version 21.2 of Parallels RAS Client.
Potential Impact
An attacker who can run low-privileged code locally on a system with the vulnerable Parallels RAS Client can escalate their privileges to SYSTEM level. This allows full control over the affected system, including the ability to execute arbitrary code with the highest privileges, potentially compromising confidentiality, integrity, and availability.
Mitigation Recommendations
Apply the official patch by upgrading to Parallels RAS Client version 21.2 or later, where this vulnerability is fixed. Until patched, restrict local code execution capabilities to trusted users only to reduce risk.
Technical Details
- Classification
- {"confidence":0.95,"severitySource":"cvss-text","classifier":"rss-v2"}
- Article Source
- {"url":"http://www.zerodayinitiative.com/advisories/ZDI-26-554/","fetched":true,"fetchedAt":"2026-08-12T20:03:30.916Z","wordCount":186}
Threat ID: 6a7cd317bf8831d5391487cb
Added to database: 08/12/2026, 20:09:59 UTC
Last enriched: 08/12/2026, 20:12:08 UTC
Last updated: 08/12/2026, 22:41:01 UTC
Views: 2
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