Affected Version(s)

Solution

Trend Micro has released the following solutions to address the issue:

These are the minimum recommended version(s) of the patches and/or builds required to address the issue. Trend Micro highly encourages customers to obtain the latest version of the product if there is a newer one available than the one listed in this bulletin.

*Please note that one of the OfficeScan XG SP1 vulnerabilities was addressed in a previous patch than the one listed above; however, it is always recommended to get the latest known version for complete mitigation.

Customers are encouraged to visit Trend Micro’s Download Center to obtain prerequisite software (such as Service Packs) before applying any of the solutions above.

Vulnerability Details

CVE-2020-24556 and CVE-2020-24562:  Trend Micro Apex One Hard Link Privilege Escalation Vulnerability (Windows)
CVSSv3: 7.8: AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
A vulnerability in Trend Micro Apex One 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.

CVE-2020-24557:  Trend Micro Apex One and OfficeScan XG Improper Access Control Privilege Escalation
CVSSv3: 7.8: AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
A vulnerability in Trend Micro Apex One and OfficeScan XG 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.
 

CVE-2020-24558:  Trend Micro Apex One and OfficeScan XG Out-of-Bounds Read Information Disclosure
CVSSv3: 5.5: AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H
A vulnerability in an Trend Micro Apex One and OfficeScan XG SP1 dll may allow an attacker to manipulate it to cause an out-of-bounds read that crashes multiple processes in the product.

An attacker must first obtain the ability to execute low-privileged code on the target system in order to exploit this vulnerability

CVE-2020-24559:  Trend Micro Apex One Hard Link Privilege Escalation Vulnerability (macOS)
CVSSv3: 7.8: AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
A vulnerability in Trend Micro Apex One on macOS may allow an attacker to manipulate a certain binary to load and run a script from a user-writable folder, which then would allow them to execute arbitrary code as root.

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 the updated macOS client for Apex One (on-premise) is available via Trend Micro's ActiveUpdate.

 

Mitigating Factors

Exploiting these type of vulnerabilities generally require that an attacker has access (physical or remote) to a vulnerable machine. In addition to timely application of patches and updated solutions, customers are also advised to review remote access to critical systems and ensure policies and perimeter security is up-to-date.

Newer versions of the operating system (e.g. Windows 10) may protect against some vulnerabilities such as hard link privilege escalations.

However, even though an exploit may require several specific conditions to be met, Trend Micro strongly encourages customers to update to the latest builds as soon as possible.

Acknowledgement

Trend Micro would like to thank the following individuals for responsibly disclosing these issues and working with Trend Micro to help protect our customers:

• @Kharosx0 working with Trend Micro's Zero Day Initiative

External Reference(s)

• ZDI-20-1093
• ZDI-20-1094
• ZDI-20-1095
• ZDI-20-1096