CVE intelligence and bounded remediation

CVE-2020-24556 — Trendmicro Apex One security vulnerability

High CVSS 7.8

A vulnerability in Trend Micro Apex One, OfficeScan XG SP1, Worry-Free Business Security 10 SP1 and Worry-Free Business Security Services on Microsoft Windows may allow an attacker to create a hard link to any file on the system, which then could be manipulated to gain a privilege escalation and code execution. 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.

Severity
High
CVSS
7.8 (3.1)
Published
2020-09-01
CISA KEV
Not currently listed
Ecosystem
windows/system
Weaknesses
CWE-59

Affected products

  • trendmicro / apex_one / 2019
  • trendmicro / apex_one / saas
  • trendmicro / worry-free_business_security / 10.0
  • trendmicro / worry-free_business_security_services

Matched remediation archetype

Path traversal, unsafe upload, and file handling

This catalog composition supplies bounded fallback guidance. Explicitly reviewed curated workflows load with the complete record below.

Check exposure

  • Trace untrusted filenames, archive entries, URLs, and path segments into read, write, include, extraction, and upload operations.
  • Identify filesystem roots, mount permissions, symbolic-link behavior, archive handling, and whether uploaded content is web-accessible or executable.
  • Review canonicalization and containment checks across supported operating systems and storage backends.

Remediate safely

  • Generate server-side storage identifiers and resolve paths beneath a fixed root using filesystem-aware containment checks.
  • Reject absolute, parent-relative, alternate-separator, device, link, and archive entries that escape the intended root.
  • Store uploads outside executable or served paths, validate type and size, and use private atomic temporary files.

Authoritative sources

Complete CVE record and remediation plan

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