CVE-2021-31838

Arbitrary command execution via environment-variable injection

Published Jun 29, 2021 · Updated Aug 3, 2024

Command injection in McAfee MVISION EDR before 3.4.0 allows remote authenticated users to execute arbitrary PowerShell commands on endpoints. The execute reaction function places administrator-controlled environment-variable content into a PowerShell command without neutralizing command syntax. MVEDR administrator privileges are required, and successful exploitation runs commands through the EDR client with effects bounded by that client's permissions.

CVSS severity9.1
Critical
EPSS probability2.09%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Command injection in McAfee MVISION EDR before 3.4.0 allows remote authenticated users to execute arbitrary PowerShell commands on endpoints. The execute reaction function places administrator-controlled environment-variable content into a PowerShell command without neutralizing command syntax. MVEDR administrator privileges are required, and successful exploitation runs commands through the EDR client with effects bounded by that client's permissions.

The record

CVE
CVE-2021-31838
Published
Jun 29, 2021
Updated
Aug 3, 2024
Vendor
McAfee
Product
McAfee MVISION Endpoint Detection and Response (MVISION EDR)
Classifications
CWE-78, T1059.001
Attack vector
adjacent
Privileges
admin

Timeline

How it unfolded

  1. Jun 29, 2021CVE publishedPublication date reported by the CVE source.
  2. Aug 3, 2024Record updatedLatest update available in the CVE record.

Exploitability

Present is not the same as exploitable

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Is a vulnerable build present?

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

  1. Affected versionversion=unspecified <3.4.0

What conditions does exploitation require?

Attack vectoradjacent
Required privilegesadmin

What is affected?

McAfee · McAfee MVISION Endpoint Detection and Response (MVISION EDR)version=unspecified <3.4.0

Published CVSS scores

8.4TrellixCVSS:3.1/AV:A/AC:L/PR:H/UI:N/S:C/C:H/I:H/A:H
9.0NIST NVDAV:N/AC:L/Au:S/C:C/I:C/A:C
9.1NIST NVDCVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:C/C:H/I:H/A:H

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.

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No observations available

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

Weakness, pattern, technique

CWE-78Improper Neutralization of Special Elements used in an OS Command ('OS Command Injection')
T1059.001Command and Scripting Interpreter: PowerShell

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

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Your stack

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