High severity · published Feb 16, 2022
CVE-2021-21958
A heap-based buffer overflow vulnerability exists in the Hword HwordApp.dll functionality of Hancom Office 2020 11.0.0.2353
7.8
CVSS
1.1%
EPSS
No
On KEV
Description
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.
CVSS vector
CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H
Attack vector
Local
Complexity
Low
Privileges
None
User interaction
Required
Confidentiality
High
Integrity
High
Availability
High
Scope
Unchanged
Exploitation
Is it being used?
Exploit prediction (EPSS)1.1% · higher than 66% of CVEs
Exploited in the wildNo evidence yet
CISA KEVNot listed
Ransomware campaign useNot known
Affected products
Which versions
HO
Hancom Office 2020 · Hancom
11.0.0.2353 · source: NVD
References
NVD
https://nvd.nist.gov/vuln/detail/CVE-2021-21958
CVE.org
https://www.cve.org/CVERecord?id=CVE-2021-21958
Exploit
https://talosintelligence.com/vulnerability_reports/TALOS-2021-1386
Exploit
https://blog.talosintelligence.com/2022/02/vuln-spotlight-.html
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