How severe is CVE-2021-33599?

CVE-2021-33599 has a CVSS 3.x base score of 4.6, rated medium severity. It is exploitable over network with low attack complexity, requires low privileges and user interaction. Impact on confidentiality is low, integrity low, and availability none.

Is CVE-2021-33599 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (33rd percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2021-33599?

CVE-2021-33599 primarily affects F-secure Atlant. In total, 4 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.

How do I fix CVE-2021-33599?

Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.

When was CVE-2021-33599 published?

CVE-2021-33599 was published on 2021-09-07 and last updated on 2026-06-17.

CVE-2021-33599

CVE-2021-33599 is a medium-severity vulnerability in F-secure Atlant with a CVSS 3.x base score of 4.6. It is not currently listed as actively exploited by CISA, and its EPSS exploit-prediction score is low. The underlying weakness is classified as CWE-835.

Key facts

Severity: Medium (CVSS 3.x base score 4.6)
CVSS v2: 4.3
EPSS exploit prediction: 0% (33rd percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-835
Affected product: F-secure Atlant
Published: 2021-09-07
Last modified: 2026-06-17

Description

A vulnerability affecting F-Secure Antivirus engine was discovered whereby scanning WIM archive file can lead to denial-of-service (infinite loop and freezes AV engine scanner). The vulnerability can be exploit remotely by an attacker. A successful attack will result in Denial-of-Service of the Anti-Virus engine.

Frequently asked questions

What is CVE-2021-33599?: A vulnerability affecting F-Secure Antivirus engine was discovered whereby scanning WIM archive file can lead to denial-of-service (infinite loop and freezes AV engine scanner). The vulnerability can be exploit remotely by an attacker. A successful attack will result in Denial-of-Service of the Anti-Virus engine.
How severe is CVE-2021-33599?: CVE-2021-33599 has a CVSS 3.x base score of 4.6, rated medium severity. It is exploitable over network with low attack complexity, requires low privileges and user interaction. Impact on confidentiality is low, integrity low, and availability none.
Is CVE-2021-33599 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (33rd percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2021-33599?: CVE-2021-33599 primarily affects F-secure Atlant. In total, 4 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.
How do I fix CVE-2021-33599?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.
When was CVE-2021-33599 published?: CVE-2021-33599 was published on 2021-09-07 and last updated on 2026-06-17.

References

Affected products (4)

cpe:2.3:a:f-secure:atlant:-:*:*:*:*:*:*:*
cpe:2.3:a:f-secure:cloud_protection_for_salesforce:-:*:*:*:*:*:*:*
cpe:2.3:a:f-secure:linux_security:-:*:*:*:*:*:*:*
cpe:2.3:a:f-secure:elements_endpoint_protection:-:*:*:*:*:*:*:*

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