Trend Micro · Apex One, OfficeScan, and Worry-Free Business Security
CVE-2020-24557
Trend Micro Multiple Products Improper Access Control Vulnerability
What it is
A vulnerability in Trend Micro Apex One and Worry-Free Business Security 10.0 SP1 on Microsoft Windows may allow an attacker to manipulate a particular product folder to disable the security temporarily, abuse a specific Windows function and attain privilege escalation. An attacker must first obtain the ability to execute low-privileged code on the target system in order to exploit this vulnerability. Please note that version 1909 (OS Build 18363.719) of Microsoft Windows 10 mitigates hard links, but previous versions are affected.
CISA: Trend Micro Apex One, OfficeScan, and Worry-Free Business Security on Microsoft Windows contain an improper access control vulnerability that may allow an attacker to manipulate a particular product folder to disable the security temporarily, abuse a specific Windows function, and attain privilege escalation.
What to do
Apply updates per vendor instructions.
Deadline for US federal agencies: May 3, 2022
More exploited flaws from Trend Micro
| Added | Vulnerability | Product | Severity | Attack chance |
|---|---|---|---|---|
| May 21, 2026 | (On-Premise) Directory Traversal | Apex One | Medium 6.7 | 13% |
| Aug 18, 2025 | OS Command Injection | Apex One | Critical 9.4 | 25% |
| Sep 21, 2023 | Remote Code Execution | Apex One and Worry-Free Business Security | High 7.2 | 4.2% |
| Sep 15, 2022 | Improper Validation | Apex One and Apex One as a Service | High 7.2 | 3.4% |
| Mar 31, 2022 | Arbitrary File Upload | Apex Central | Critical 9.8 | 19% |
| Nov 3, 2021 | Remote Code Execution | Apex One and OfficeScan | High 8.8 | 11% |
| Nov 3, 2021 | Multiple Products Content Validation Escape | Apex One, OfficeScan and Worry-Free Business Security Agents | High 8.8 | 6.2% |
| Nov 3, 2021 | Authentication Bypass | Apex One and OfficeScan | Critical 9.8 | 12% |
Sources: Known Exploited Vulnerabilities (CISA, public domain), CVE records (cve.org) and EPSS (FIRST). The chance of attacks is the EPSS estimate that someone will try to exploit the flaw in the next 30 days.