CVE-2021-31838
Official description Straight from the sourceThe vendor's or NVD's own wording, published unedited. Authoritative, but often terse — it says what broke, rarely what to do.
NVD · uneditedA command injection vulnerability in MVISION EDR (MVEDR) prior to 3.4.0 allows an authenticated MVEDR administrator to trigger the EDR client to execute arbitrary commands through PowerShell using the EDR functionality 'execute reaction'.
Technical summary Written by usOur analysis, written from the advisory, the CVSS vector and the affected-version data. It adds context the advisory leaves out, and never invents facts that are not in the source.
dbcve analysis · high confidenceMVISION EDR prior to 3.4.0 contains a command injection vulnerability in the 'execute reaction' feature that allows authenticated administrator accounts to trigger the EDR client to execute arbitrary PowerShell commands. The feature, designed for endpoint response actions, fails to properly sanitize input allowing an attacker with admin credentials to achieve remote code execution on managed endpoints.
Verify against the referenced sources before acting — the references below are authoritative for this CVE, this summary is not.
Affected products & versions What the vendor confirmedThe version ranges the vendor confirmed as vulnerable. If your version sits inside a range here, treat yourself as exposed until you have upgraded.
NVD · CPE data< 3.4.0CVSS breakdown How the score is builtThe industry scoring standard. It rates how the flaw is reached, what it takes to exploit, and what an attacker gains — the score is derived from those, not the other way round.
From the vector- Attack vector
- Network
- Complexity
- Low
- Privileges
- High
- User interaction
- None
- Scope
- Changed
- Confidentiality
- High
- Integrity
- High
- Availability
- High
CVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:C/C:H/I:H/A:H
Am I affected? How to checkSteps we derive from the advisory and the affected-version data, so you can decide whether this CVE reaches your setup. They are a guide, not a scan — your own configuration is the authority.
dbcve checksWork through these to decide whether this CVE applies to you.
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Identify if MVISION EDR is installedCheck the installed software on the management server or endpoints for MVISION EDR or McAfee EDR components. On Windows, review Add/Remove Programs or check for MVISION services in Services.msc.Affected if MVISION EDR is present and version cannot be determined or is below 3.4.0
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Determine the installed version of MVISION EDRUse the MVISION EDR console or check the installed package version on the management server. The version is typically visible in the console dashboard, about section, or in the installed software metadata.Affected if The version number is lower than 3.4.0 (for example, 3.3.x, 3.2.x, etc.)
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Verify the 'execute reaction' feature exists and is accessibleLog into the MVISION EDR console as an administrator and navigate to the endpoint response or reaction feature area. Confirm the 'execute reaction' or similar endpoint response functionality is present and enabled.Affected if The 'execute reaction' feature is present and available to administrator accounts
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Check for suspicious or unauthorized endpoint response actionsReview the MVISION EDR activity logs, endpoint response history, or audit logs for any execute reaction commands that were run, especially those with unusual or unexpected PowerShell command patterns.Affected if Logs show execute reaction actions with commands that were not explicitly authorized or expected, or commands containing suspicious PowerShell syntax
You are affected if MVISION EDR is installed with a version lower than 3.4.0 and the 'execute reaction' feature is accessible to administrator accounts in your environment.
Generated from the published advisory. Verify against your own configuration.
Remediation Closing itWhat it takes to close this. Where a vendor fix exists we point at it; where none exists we say so plainly, and can build one. Effort estimates are scoped from the advisory, not from your codebase.
dbcve · scoped3.4.0
Upgrade MVISION EDR to version 3.4.0 or later to patch the command injection vulnerability. Limit administrator access to trusted personnel and implement least-privilege principles for EDR administrative accounts.
MVISION EDR 3.4.0 or later
- 1. Identify the current MVISION EDR version by checking the installed client or admin console
- 2. Download MVISION EDR version 3.4.0 or later from the official McAfee download portal or through your authorized distribution channel
- 3. Review McAfee MVISION EDR upgrade documentation for any pre-upgrade requirements or compatibility checks
- 4. Create a backup of the current configuration and ensure you have a rollback plan
- 5. Apply the upgrade to the MVISION EDR server and/or distributed clients as per McAfee's deployment procedures
- 6. After upgrade, verify the installation by checking the version number in the admin console
- 7. Confirm that the 'execute reaction' functionality now properly sanitizes commands to prevent injection
Generated from the published advisory — verify against the referenced sources before acting.
- Consultation2.0 h
- Implementation1.0 h
- Testing4.0 h
- Review / QA2.0 h
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Scan for this in your stack
Free · runs locallyCheck whether your project pulls in CVE-2021-31838 — or any other known-vulnerable package — straight from your lock files. Free and open source; it runs locally and uploads nothing.
References Go to the primary sourcePrimary sources — vendor advisories, patches and trackers. Where our summary and a reference disagree, the reference wins.
Primary sourcesPractitioner notes
ContributedPeer-ranked notes from engineers who’ve handled CVE-2021-31838 in production — separate from our analysis above.
The advisory tells you what broke. It rarely tells you what actually worked. If you’ve dealt with this one, that detail is what the next engineer is searching for.
- The version that genuinely resolved it — not the one the vendor claimed
- A config change or rule that shut the vector down
- A gotcha in the upgrade path that cost you an afternoon
No notes yet
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- Version or environment caveats, and links to real fixes
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