dbcve.org
Actively exploited in the wild. This CVE is on the CISA Known Exploited Vulnerabilities list — treat remediation as urgent. Federal remediation due by 17 Nov 2021.
OfficescanApplication · Trendmicro

CVE-2021-36742

HIGH · 7.8 CVSS v3.1 Published 2021-07-29
Mitigation only
No fix yet — a mitigation exists. There is no fixed release. A documented workaround reduces exposure in the meantime.
See remediation →
96/100
Remediation priority · Urgent
In the wild Zero-click

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 · unedited
A improper input validation vulnerability in Trend Micro Apex One, Apex One as a Service, OfficeScan XG and Worry-Free Business Security 10.0 SP1 allows a local attacker to escalate privileges on affected installations. Please note: an attacker must first obtain the ability to execute low-privileged code on the target system in order to exploit this vulnerability.

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 confidence

This is a local privilege escalation vulnerability in multiple Trend Micro endpoint security products (Apex One, OfficeScan XG, Worry-Free Business Security). The improper input validation flaw allows an attacker who has already achieved low-privileged code execution on the target system to elevate to SYSTEM/root privileges, bypassing existing privilege boundaries.

MitigationApply the vendor-released patches for CVE-2021-36742 to all affected Trend Micro installations. Since this requires prior low-privileged code execution, also ensure strict access controls and monitoring for any anomalous local code execution.

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
OfficescanApplication
Affected:= xg
Officescan Business SecurityApplication
Affected:= 10.0
Apex OneApplication
Affected:= 2019
Worry Free Business SecurityApplication
Affected:= 10.0

CVSS 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
Local
Complexity
Low
Privileges
Low
User interaction
None
Scope
Unchanged
Confidentiality
High
Integrity
High
Availability
High

CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/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 checks

Work through these to decide whether this CVE applies to you.

  1. Identify installed Trend Micro product
    Check the Windows registry under HKLM\SOFTWARE\TrendMicro\ for product keys, or look in Add/Remove Programs for installed Trend Micro security software. Common display names include 'Trend Micro Apex One', 'Trend Micro OfficeScan', or 'Trend Micro Worry-Free Business Security'.
    Affected if Any of these three products are installed.
  2. Determine installed product version
    Check the registry key HKLM\SOFTWARE\TrendMicro\<ProductName>\CurrentVersion for the version string, or right-click the Trend Micro system tray icon and select 'About' to view version information.
    Affected if Version matches: OfficeScan XG (any subversion), OfficeScan Business Security 10.0, Apex One 2019 (any patch), or Worry-Free Business Security 10.0.
  3. Confirm security service is running
    Open Services.msc and locate the Trend Micro service (commonly 'Trend Micro Apex One Security Controller', 'OfficeScan NT Listener', or 'Trend Micro Security Server'). Verify its Status is 'Running'.
    Affected if The vulnerable product service is actively running, which is required for the privilege escalation to be exploitable.
  4. Check for low-privileged user access
    Verify that non-admin users exist on the system by running 'net user' at command prompt, and confirm these users are not members of the Administrators group.
    Affected if Low-privileged local or domain users exist on the system, as the CVE requires an attacker with ability to execute low-privileged code.

You are affected if a Trend Micro endpoint security product (Apex One 2019, OfficeScan XG, OfficeScan Business Security 10.0, or Worry-Free Business Security 10.0) is installed with its service running on a system that permits low-privileged user access.

Generated from the published advisory. Verify against your own configuration.

Check your environment

Paste your version and any relevant configuration and it will be compared against the affected criteria above. Do not include secrets or credentials.

AI-assisted, checked against the advisory. Informational, not a guarantee.

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 · scoped
Mitigation available No clean upgrade yet — mitigate in the meantime
Mitigation

Apply the vendor-released patches for CVE-2021-36742 to all affected Trend Micro installations. Since this requires prior low-privileged code execution, also ensure strict access controls and monitoring for any anomalous local code execution.

Recommended fix Moderate confidence

Upgrade to the latest supported version or apply the latest security patch for your specific Trend Micro product (Apex One 2019 SP1 or later, OfficeScan XG SP1 with latest patches, or Worry-Free Business Security 10.0 SP1 with latest patches)

  1. 1. Identify the currently installed version of the affected Trend Micro product (Apex One 2019, OfficeScan XG, OfficeScan Business Security 10.0, or Worry-Free Business Security 10.0)
  2. 2. Navigate to the Trend Micro Customer Portal (success.trendmicro.com) or contact Trend Micro Technical Support
  3. 3. Locate the security patch or service pack that addresses CVE-2021-36742
  4. 4. Download and apply the appropriate patch for your specific product version
  5. 5. Alternatively, upgrade to the latest supported version of the product which contains the security fix
  6. 6. Verify the patch was applied successfully by checking the product version and reviewing installed updates
Caveat Review release notes for any compatibility considerations or configuration changes required after patching

Generated from the published advisory — verify against the referenced sources before acting.

Fix this in Officescan Exploited in the wild — priority engagement
  • Consultation2.0 h
  • Implementation2.0 h
  • Testing2.0 h
  • Review / QA1.0 h
7.0 hours of engineering $1,240
Get help mitigating

An estimate, not a bill — we confirm scope with you before any work starts. Need it this week? Rush from $1,984.

Scan for this in your stack

Free · runs locally
dbcve dependency scanner

Check whether your project pulls in CVE-2021-36742 — or any other known-vulnerable package — straight from your lock files. Free and open source; it runs locally and uploads nothing.

Get it on GitHub Scan in the browser

References Go to the primary sourcePrimary sources — vendor advisories, patches and trackers. Where our summary and a reference disagree, the reference wins.

Primary sources

Practitioner notes

Contributed

Peer-ranked notes from engineers who’ve handled CVE-2021-36742 in production — separate from our analysis above.

No notes yet

Be the first to add a field note for this CVE — a mitigation you’ve verified, a version caveat, or a link to a working fix. Sign in above to contribute.

What this is

A place for practitioners to share what actually worked: a mitigation you’ve tested, a configuration change, a version- or environment-specific caveat, or a link to a verified patch. The most useful notes rise to the top as peers upvote them, so the signal stays high.

What belongs here
  • Verified mitigations, workarounds, and config changes
  • Version or environment caveats, and links to real fixes
  • No weaponised exploit code, or anything meant to cause harm
  • No spam, self-promotion, credentials, or personal data