How severe is CVE-2023-43761?

CVE-2023-43761 has a CVSS 3.x base score of 7.5, rated high severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is none, integrity none, and availability high.

Is CVE-2023-43761 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (41st percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2023-43761?

CVE-2023-43761 primarily affects F-secure Linux Protection. In total, 7 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.

How do I fix CVE-2023-43761?

Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its high severity, prioritise patching exposed systems.

When was CVE-2023-43761 published?

CVE-2023-43761 was published on 2023-09-22 and last updated on 2026-06-17.

CVE-2023-43761

CVE-2023-43761 is a high-severity vulnerability in F-secure Linux Protection with a CVSS 3.x base score of 7.5. 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: High (CVSS 3.x base score 7.5)
EPSS exploit prediction: 1% (41st percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-835
Affected product: F-secure Linux Protection
Published: 2023-09-22
Last modified: 2026-06-17

Description

Certain WithSecure products allow Denial of Service (infinite loop). This affects WithSecure Client Security 15, WithSecure Server Security 15, WithSecure Email and Server Security 15, WithSecure Elements Endpoint Protection 17 and later, WithSecure Client Security for Mac 15, WithSecure Elements Endpoint Protection for Mac 17 and later, Linux Security 64 12.0 , Linux Protection 12.0, and WithSecure Atlant (formerly F-Secure Atlant) 1.0.35-1.

Frequently asked questions

What is CVE-2023-43761?: Certain WithSecure products allow Denial of Service (infinite loop). This affects WithSecure Client Security 15, WithSecure Server Security 15, WithSecure Email and Server Security 15, WithSecure Elements Endpoint Protection 17 and later, WithSecure Client Security for Mac 15, WithSecure Elements Endpoint Protection for Mac 17 and later, Linux Security 64 12.0 , Linux Protection 12.0, and WithSecure Atlant (formerly F-Secure Atlant) 1.0.35-1.
How severe is CVE-2023-43761?: CVE-2023-43761 has a CVSS 3.x base score of 7.5, rated high severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is none, integrity none, and availability high.
Is CVE-2023-43761 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (41st percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2023-43761?: CVE-2023-43761 primarily affects F-secure Linux Protection. In total, 7 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.
How do I fix CVE-2023-43761?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its high severity, prioritise patching exposed systems.
When was CVE-2023-43761 published?: CVE-2023-43761 was published on 2023-09-22 and last updated on 2026-06-17.

References

Affected products (7)

cpe:2.3:a:f-secure:linux_protection:12.0:*:*:*:*:*:*:*
cpe:2.3:a:f-secure:linux_security_64:12.0:*:*:*:*:*:*:*
cpe:2.3:a:f-secure:atlant:1.0.35-1:*:*:*:*:*:*:*
cpe:2.3:a:f-secure:client_security:15.00:*:*:*:*:*:*:*
cpe:2.3:a:f-secure:elements_endpoint_protection:*:*:*:*:*:*:*:*
cpe:2.3:a:f-secure:email_and_server_security:15.00:*:*:*:*:*:*:*
cpe:2.3:a:f-secure:server_security:15.00:*:*:*:*:*:*:*

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