CVE-2021-36741Known exploitationNetwork attack vector

Authenticated arbitrary file upload

Published Jul 29, 2021 · Updated Oct 21, 2025

Arbitrary file upload in affected Trend Micro endpoint products allows remote authenticated users to write files through the management console. Trend Micro identifies improper input validation but has not published the affected upload handler or how it fails to constrain file names, paths, or types. Access to the management console is required; a successful upload can alter server files, and Trend Micro observed the flaw used with a local privilege-escalation flaw.

CVSS severity7.1
High
EPSS probability4.95%
Next 30 days · Sep 16, 2026
Known exploitationReported
Based on sourced intelligence
Hinoki checkNot available
Coverage for this vulnerability

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Summary

What happened

Arbitrary file upload in affected Trend Micro endpoint products allows remote authenticated users to write files through the management console. Trend Micro identifies improper input validation but has not published the affected upload handler or how it fails to constrain file names, paths, or types. Access to the management console is required; a successful upload can alter server files, and Trend Micro observed the flaw used with a local privilege-escalation flaw.

The record

CVE
CVE-2021-36741
Published
Jul 29, 2021
Updated
Oct 21, 2025
Vendor
Trend Micro
Product
Trend Micro Worry-Free Business Security
Classifications
CWE-434, T1190
Attack vector
network
Privileges
authenticated

Timeline

How it unfolded

  1. Jul 29, 2021CVE publishedPublication date reported by the CVE source.
  2. Oct 21, 2025Record 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=10.0 SP1

What conditions does exploitation require?

Attack vectornetwork
Required privilegesauthenticated

What is affected?

Trend Micro · Trend Micro Worry-Free Business Securityversion=10.0 SP1
Trend Micro · Trend Micro Apex Oneversion=2019, SaaS
Trend Micro · Trend Micro OfficeScanversion=XG SP1

Published CVSS scores

7.1Trend MicroCVSS:3.0/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:L/A:H
8.8NIST NVDCVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
8.8CISA-ADPCVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
6.5NIST NVDAV:N/AC:L/Au:S/C:P/I:P/A:P

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 9, 2026Sep 15, 2026
Latest reporting daySep 15, 2026
Latest daily unique IPsUnavailable
Prior 30-day averageUnavailable
SourceShadowserver honeypots (KEV)
Vectornetwork
Privilegesauthenticated
Known exploitationReported
Public exploitUnconfirmed

Weakness, pattern, technique

CWE-434Unrestricted Upload of File with Dangerous Type
T1190Exploit Public-Facing Application

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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