Is CVE-2026-13121 exploited in the wild?

No. Junglewise Threat Intelligence has no report of CVE-2026-13121 being exploited in the wild.

How severe is CVE-2026-13121?

High severity, with a CVSS score of 7.8, published 20 August 2026.

Which products and versions are affected?

Parallels RAS Client before 21.2.

Is there a fix for CVE-2026-13121?

A patch was published on 2026-08-11: Fixed in version 21.2; coordinated public release of advisory Junglewise finds every place you run it, drafts the upgrade and applies it once you approve.

How is CVE-2026-13121 attacked?

It is attacked with local access.

Am I affected by CVE-2026-13121?

Check whether you run Parallels RAS Client at an affected version. Junglewise does that check for you around the clock: connect your code, cloud and domains, and it matches new vulnerabilities like this one against what you actually run and tells you when one reaches you.

CVE-2026-13121: Parallels RAS Client privilege escalation in RDP Backend Service

CVE-2026-13121 · Severity: high · CVSS 7.8 · Published 2026-08-20

Parallels RAS Client is a remote access software component that enables secure desktop connections. A flaw in its RDP Backend Service allows local attackers to escalate privileges to SYSTEM level, potentially gaining full control of affected systems. Exploitation requires an attacker to first obtain low-privilege code execution on the target machine, but once achieved, the vulnerability enables complete system compromise and arbitrary code execution.

Technologies: Parallels RAS Client. Vendors: Parallels.

Quick answers

Is CVE-2026-13121 exploited in the wild?: No. Junglewise Threat Intelligence has no report of CVE-2026-13121 being exploited in the wild.
How severe is CVE-2026-13121?: High severity, with a CVSS score of 7.8, published 20 August 2026.
Which products and versions are affected?: Parallels RAS Client before 21.2.
Is there a fix for CVE-2026-13121?: A patch was published on 2026-08-11: Fixed in version 21.2; coordinated public release of advisory Junglewise finds every place you run it, drafts the upgrade and applies it once you approve.
How is CVE-2026-13121 attacked?: It is attacked with local access.
Am I affected by CVE-2026-13121?: Check whether you run Parallels RAS Client at an affected version. Junglewise does that check for you around the clock: connect your code, cloud and domains, and it matches new vulnerabilities like this one against what you actually run and tells you when one reaches you.

Technical details

This vulnerability is a local privilege escalation flaw in the Parallels RAS Client RDP Backend Service, caused by an exposed dangerous function. The vulnerability requires an attacker to have local access and the ability to execute code in a low-privilege context (PR:L). Once triggered, the flaw allows arbitrary code execution in the SYSTEM security context (C:H/I:H/A:H), providing complete system compromise. No user interaction is required (UI:N), and the scope is unchanged (S:U). The vulnerability was fixed in version 21.2 of Parallels RAS Client.

Affected products

Parallels RAS Client before 21.2

Timeline

2026-02-25: disclosed: Vulnerability reported to vendor
2026-08-11: patched: Fixed in version 21.2; coordinated public release of advisory

References

https://www.zerodayinitiative.com/advisories/ZDI-26-554/

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