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Vulnerability record · CVE-2021-40833 · published 26 November 2021

CVE-2021-40833: F-secure atlant improper resource shutdown vulnerability

F Secure · Atlant

A vulnerability affecting F-Secure antivirus engine was discovered whereby unpacking UPX file can lead to denial-of-service. The vulnerability can be exploited remotely by an attacker. A successful attack will result in denial-of-service of the antivirus engine.

5.5 CVSS 3.1 Medium EPSS 0.41% · top 67.7% CWE-404 · Improper resource shutdown
5.5CVSS 3.1 base score, v2 4.3
0.41%EPSS exploitation probability, 30 days
NoNot in CISA KEV
5Affected product versions listed by NVD
4References
17 Jun 2026Last modified by NVD

Description

A vulnerability affecting F-Secure antivirus engine was discovered whereby unpacking UPX file can lead to denial-of-service. The vulnerability can be exploited remotely by an attacker. A successful attack will result in denial-of-service of the antivirus engine.

CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:N/I:N/A:H

Affected products

5 vulnerable configurations from NVD's CPE data, grouped by vendor and product.

References

LinkTags
https://www.f-secure.com/en/business/programs/vulnerability-reward-program/hall-of-fame Vendor Advisory
https://www.f-secure.com/en/business/support-and-downloads/security-advisories/cve-2021-40833 Vendor Advisory
https://www.f-secure.com/en/business/programs/vulnerability-reward-program/hall-of-fame Vendor Advisory
https://www.f-secure.com/en/business/support-and-downloads/security-advisories/cve-2021-40833 Vendor Advisory

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Related vulnerabilities

Same products first, then exploited flaws of the same weakness class.

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Source: NIST National Vulnerability Database (record CVE-2021-40833), CISA KEV, FIRST EPSS (scores of 2026-09-29). This page is refreshed as NVD updates the record.