CVE-2021-34868

Guest-to-hypervisor code execution via uncontrolled allocation

Published Jan 25, 2022 · Updated Aug 4, 2024

Privilege escalation in Parallels Desktop 16.1.3-49160 allows local users to execute arbitrary code in the hypervisor context. The Toolgate component fails to validate user-supplied data before using it to size a memory allocation, allowing an excessive allocation. Exploitation requires low-privileged code execution inside a target guest and crosses the guest boundary into the hypervisor.

CVSS severity7.8
High
EPSS probability0.42%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
Coverage for this vulnerability

See if you're affected

Explore vulnerability checks for your environment with Hinoki.

Book a demo

Summary

What happened

Privilege escalation in Parallels Desktop 16.1.3-49160 allows local users to execute arbitrary code in the hypervisor context. The Toolgate component fails to validate user-supplied data before using it to size a memory allocation, allowing an excessive allocation. Exploitation requires low-privileged code execution inside a target guest and crosses the guest boundary into the hypervisor.

The record

CVE
CVE-2021-34868
Published
Jan 25, 2022
Updated
Aug 4, 2024
Vendor
Parallels
Product
Parallels Desktop
Classifications
CWE-789, T1068
Attack vector
local
Privileges
authenticated

Timeline

How it unfolded

  1. Jan 25, 2022CVE publishedPublication date reported by the CVE source.
  2. Aug 4, 2024Record updatedLatest update available in the CVE record.

Exploitability

Present is not the same as exploitable

Compare your product and version with the public record. A matching version still requires validation against your environment.

Is a vulnerable build present?

Compare these published version ranges with your installed build and any vendor patches.

  1. Affected versionversion=16.1.3-49160

What conditions does exploitation require?

Attack vectorlocal
Required privilegesauthenticated

What is affected?

Parallels · Parallels Desktopversion=16.1.3-49160

Published CVSS scores

7.8Zero Day InitiativeCVSS:3.0/AV:L/AC:H/PR:L/UI:N/S:C/C:H/I:H/A:H
8.8NIST NVDCVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:C/C:H/I:H/A:H
7.2NIST NVDAV:L/AC:L/Au:N/C:C/I:C/A:C

CVSS describes severity. EPSS estimates exploitation probability.

Attacks

What attackers are doing with it

Daily unique IPs observed by Shadowserver honeypots for known exploited vulnerabilities (KEVs). Missing observations do not establish an absence of attacks.

Daily unique IPsNo honeypot observations are available for this CVE in the selected window.

No observations available

Sep 10, 2026Sep 16, 2026
Latest reporting daySep 16, 2026
Latest daily unique IPsUnavailable
Prior 30-day averageUnavailable
SourceShadowserver honeypots (KEV)
Vectorlocal
Privilegesauthenticated
Known exploitationUnconfirmed
Public exploitUnconfirmed

Weakness, pattern, technique

CWE-789Memory Allocation with Excessive Size Value
T1068Exploitation for Privilege Escalation

Public exploit references

No public exploit references are available in this record.

Labels summarize the accepted research assessment. They do not indicate a test against your environment.

Technologies

Your stack

See the directory against your own environment.

Your stack

Check the software in your environment

Book a demo to see how Hinoki identifies affected software and validates exploitability in your environment.

Book a demo