CVE-2021-33602

Name: CVE-2021-33602
Creator: NVD / NIST
Published: 2021-10-06T10:15:07.823+00:00
License: https://creativecommons.org/publicdomain/zero/1.0/

MEDIUMCVSS 5.3/10EPSS 0.56%

Last modified Jun 17, 2026

CVE-2021-33602 is a medium-severity vulnerability rated 5.3/10 on the CVSS scale. A vulnerability affecting the F-Secure Antivirus engine was discovered when the engine tries to unpack a zip archive (LZW decompression method), and this can crash the scanning engine. The vulnerability can be exploited remotely by an attacker. EPSS estimates a 0.56% chance of exploitation in the next 30 days.

Description

A vulnerability affecting the F-Secure Antivirus engine was discovered when the engine tries to unpack a zip archive (LZW decompression method), and this can crash the scanning engine. The vulnerability can be exploited remotely by an attacker. A successful attack will result in Denial-of-Service of the Anti-Virus engine.

Metrics

CVSS 3.1

5.3/10

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

EPSS Probability

0.56%

42.5th percentile

Probability of exploitation in the next 30 days. Learn more

Affected Software

Vendor	Product	Versions
F-Secure	Atlant	All versions
F-Secure	Cloud Protection	All versions
F-Secure	Internet Gatekeeper	All versions
F-Secure	Linux Security	All versions

References

https://www.f-secure.com/en/business/support-and-downloads/security-advisoriesVendor Advisory
https://www.f-secure.com/en/business/support-and-downloads/security-advisoriesVendor Advisory

Timeline

Published: Oct 6, 2021
Last Modified: Jun 17, 2026
Status: Modified

Frequently Asked Questions

What is CVE-2021-33602?

How severe is CVE-2021-33602?

CVE-2021-33602 has a CVSS score of 5.3/10 (MEDIUM severity). The EPSS model estimates a 0.56% probability of exploitation in the next 30 days.

How do I fix CVE-2021-33602?

Check the vendor references and advisories linked above for patched versions and mitigation guidance. You can also run a Strix scan to test if your systems are affected.

Are you affected by CVE-2021-33602?

Run a free Strix scan to check your systems for this vulnerability.

Scan your code now

Source: NVD / NIST