How severe is CVE-2023-23581?

CVE-2023-23581 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-2023-23581 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (53rd percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2023-23581?

CVE-2023-23581 primarily affects Softether Vpn. In total, 2 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.

How do I fix CVE-2023-23581?

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-2023-23581 published?

CVE-2023-23581 was published on 2023-10-12 and last updated on 2026-06-17.

CVE-2023-23581

CVE-2023-23581 is a high-severity vulnerability in Softether Vpn 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-125.

Key facts

Severity: High (CVSS 3.x base score 7.5)
EPSS exploit prediction: 1% (53rd percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-125
Affected product: Softether Vpn
Published: 2023-10-12
Last modified: 2026-06-17

Description

A denial-of-service vulnerability exists in the vpnserver EnSafeHttpHeaderValueStr functionality of SoftEther VPN 5.01.9674 and 5.02. A specially crafted network packet can lead to denial of service.

Frequently asked questions

What is CVE-2023-23581?: A denial-of-service vulnerability exists in the vpnserver EnSafeHttpHeaderValueStr functionality of SoftEther VPN 5.01.9674 and 5.02. A specially crafted network packet can lead to denial of service.
How severe is CVE-2023-23581?: CVE-2023-23581 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-2023-23581 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (53rd percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2023-23581?: CVE-2023-23581 primarily affects Softether Vpn. In total, 2 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.
How do I fix CVE-2023-23581?: 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-2023-23581 published?: CVE-2023-23581 was published on 2023-10-12 and last updated on 2026-06-17.

References

Affected products (2)

cpe:2.3:a:softether:vpn:5.01.9674:*:*:*:*:*:*:*
cpe:2.3:a:softether:vpn:5.02:*:*:*:*:*:*:*

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