SYSTEM code execution via exposed function
Published Aug 20, 2026 · Updated Aug 20, 2026
Privilege escalation in Parallels Client 21.0.26296 allows local users to execute code as SYSTEM via the RAS RDP Backend Service. ZDI reports an exposed dangerous function in that service, and Parallels states the fix enforces digital signature verification of installers and of the calling process, indicating that privileged service actions were reachable from insufficiently trusted local callers. Exploitation requires prior low-privileged code execution on the host and is bounded to local access, but successful abuse yields full SYSTEM control.
Summary
What happened
Privilege escalation in Parallels Client 21.0.26296 allows local users to execute code as SYSTEM via the RAS RDP Backend Service. ZDI reports an exposed dangerous function in that service, and Parallels states the fix enforces digital signature verification of installers and of the calling process, indicating that privileged service actions were reachable from insufficiently trusted local callers. Exploitation requires prior low-privileged code execution on the host and is bounded to local access, but successful abuse yields full SYSTEM control.
The record
- CVE
- CVE-2026-18263
- Published
- Aug 20, 2026
- Updated
- Aug 20, 2026
- Vendor
- Parallels
- Product
- Parallels Client
- Classifications
- CWE-749, T1068
- Attack vector
- local
- Privileges
- authenticated
Timeline
How it unfolded
- Aug 20, 2026CVE publishedPublication date reported by the CVE source.
- Aug 20, 2026Record updatedLatest update available in the CVE record.
Exploitability
Present is not the same as exploitable
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Is a vulnerable build present?
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- Affected versionversion=21.0.26296
What conditions does exploitation require?
What is affected?
Published CVSS scores
CVSS describes severity. EPSS estimates exploitation probability.
Attacks
What attackers are doing with it
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Weakness, pattern, technique
Public exploit references
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Technologies
Your stack
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Your stack
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