Buffer overflow in Hancom Office 2020

CVE-2021-21958

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.

Vulnerability class: Buffer Overflow

Published · last modified .

CVSS v3 metric

CVSS v3 base score 7.8 (High). Vector: CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H.

EPSS exploit prediction

EPSS: 0.011 (64.3th percentile), scored .

Low probability of exploitation in the next 30 days, but still tracked. 64th percentile — 64.3% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.

EPSS trend (30 days)EPSS over the last 30 days for CVE-2021-21958: held from 0.011 to 0.011.

EPSS over last 30 days · oldest: 0.011 · newest: 0.011 · change: 0.000

Affected products

  • Hancom Office 2020 — versions 11.0.0.2353
  • Hancom — versions Hancom Office 2020 11.0.0.2353

Weakness classification (CWE)

References

Frequently asked questions

What is CVE-2021-21958?
CVE-2021-21958 is a high-severity vulnerability in Hancom Office 2020, classified under Heap-based Buffer Overflow. CVSS score: 7.8/10. Published 2022-02-16.
How severe is CVE-2021-21958?
High severity. CVSS v3 base score is 7.8 out of 10.