CVE intelligence and bounded remediation

CVE-2021-27243 — This vulnerability allows local attackers to escalate privileges on affected installations of Parallels Desktop 16.0.1-48919

High CVSS 8.8

This vulnerability allows local attackers to escalate privileges on affected installations of Parallels Desktop 16.0.1-48919. An attacker must first obtain the ability to execute low-privileged code on the target guest system in order to exploit this vulnerability. The specific flaw exists within the Toolgate component. The issue results from the lack of proper validation of user-supplied data, which can result in an integer overflow before allocating a buffer. An attacker can leverage this vulnerability to escalate privileges and execute arbitrary code in the context of the hypervisor. Was ZDI-CAN-11924.

Severity
High
CVSS
8.8 (3.1)
Published
2021-03-29
CISA KEV
Not currently listed
Ecosystem
software/application
Weaknesses
CWE-190

Affected products

  • parallels / parallels_desktop / 16.0.1

Matched remediation archetype

Command, code, expression, and template injection

This catalog composition supplies bounded fallback guidance. Explicitly reviewed curated workflows load with the complete record below.

Check exposure

  • Trace untrusted values to process execution, interpreters, evaluators, template engines, dynamic imports, and administrative scripting features.
  • Determine whether the affected path is reachable across each trust boundary and which service account or host privilege it inherits.
  • Review configuration for optional execution features, unsafe compatibility modes, and shell invocation.

Remediate safely

  • Replace string-built commands or evaluated code with fixed operations and structured argument APIs that do not invoke a shell.
  • Use strict allowlists for operation identifiers and reject unexpected input before it reaches any interpreter.
  • Update the affected component and add inert regression tests covering metacharacters, encoding variants, and alternate request paths.

Authoritative sources

Complete CVE record and remediation plan

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