CVE-2021-26608 : Security Advisory and Response

An arbitrary file download and execution vulnerability was found in the HShell.dll of handysoft Co., Ltd groupware ActiveX module due to missing support for integrity check of download URL or downloaded file hash.

Understanding CVE-2021-26608

This CVE identifies an arbitrary file download and execution vulnerability in the HShell.dll of handysoft, impacting Windows systems.

What is CVE-2021-26608?

The CVE-2021-26608 involves an ActiveX module in handysoft groupware with a vulnerability that allows attackers to download and execute files without proper integrity checks.

The Impact of CVE-2021-26608

The impact of this vulnerability is rated as HIGH severity with a CVSS base score of 8.8, affecting confidentiality, integrity, and availability of the system.

Technical Details of CVE-2021-26608

This section provides detailed technical information about the vulnerability.

Vulnerability Description

The vulnerability lies in the HShell.dll component of handysoft, allowing attackers to download and execute arbitrary files.

Affected Systems and Versions

The vulnerability affects Windows systems using specific versions of HShell.dll, including 1.7.4.5, 2.0.3.5, and 4.0.1.6.

Exploitation Mechanism

Attackers can exploit this vulnerability by leveraging the ActiveX module to download and execute malicious files without proper integrity verification.

Mitigation and Prevention

To protect systems from CVE-2021-26608, immediate actions and long-term security measures are essential.

Immediate Steps to Take

Disable the ActiveX module in handysoft groupware to prevent exploitation.
Implement network controls to restrict download capabilities.

Long-Term Security Practices

Regularly update and patch the affected software to address the vulnerability.
Train users on recognizing and avoiding potentially harmful downloads.

Patching and Updates

Check with handysoft for patches or updates that address the integrity check issue in HShell.dll.