What’s Vulnerable › Vulnerabilities

CVE-2021-33603: Denial-of-Service (DoS) Vulnerability

• Severity: medium (CVSS 6.5 v3.1)
• Exploited in the wild: not listed in CISA KEV
• EPSS: 0.6% probability of exploitation in the next 30 days
• Public exploit or detection template: none known
• Published: 2021-10-08 · updated 2026-06-17

Description

A Denial-of-Service (DoS) vulnerability was discovered in F-Secure Atlant whereby the AVPACK module component used in certain F-Secure products can crash while scanning a fuzzed files. The exploit can be triggered remotely by an attacker. A successful attack will result in Denial-of-Service (DoS) of the Anti-Virus engine.

Affected products

• F-Secure All F-Secure Endpoint Protection products on Windows and Mac F-Secure Linux Security (32-bit) F-Secure Linux Se: all versions
• F-Secure Cloud Protection For Salesforce: all versions
• F-Secure Elements Endpoint Detection And Response: all versions
• F-Secure and WithSecure All F-Secure and WithSecure Endpoint Protection Products for Windows: all versions
• F-Secure Elements For Microsoft 365: all versions
• F-Secure Internet Gatekeeper: all versions
• F-Secure Linux Security: all versions

References

• https://www.f-secure.com/en/business/programs/vulnerability-reward-program/hall-of-fame
• https://www.f-secure.com/en/business/support-and-downloads/security-advisories/cve-2021-33603
• https://www.f-secure.com/en/business/programs/vulnerability-reward-program/hall-of-fame
• https://www.f-secure.com/en/business/support-and-downloads/security-advisories/cve-2021-33603

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