CVE-2021-21958: Hancom Office 2020

High severity, CVSS 7.8. EPSS: 1.1% chance of exploitation in the next 30 days.

A heap-based buffer overflow vulnerability exists in the Hword HwordApp.dll functionality of Hancom Office 2020 11.0.0.2353. A specially-crafted malformed file can lead to memory corruption and potential arbitrary code execution. An attacker can provide a malicious file to trigger this vulnerability.

Affected products

• Hancom Hancom Office 2020: version 11.0.0.2353 only

Published 2022-02-16. Last modified 2026-06-17.