CVE-2021-26608: Handysoft Hshell

Critical severity, CVSS 9.8. EPSS: 0.6% chance of exploitation in the next 30 days.

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

Affected products

• Handysoft Hshell: version 1.7.4.5 only; version 2.0.3.5 only; version 4.0.1.6 only

Published 2021-09-09. Last modified 2026-06-17.