How severe is CVE-2023-22308?

CVE-2023-22308 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-2023-22308 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (50th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2023-22308?

CVE-2023-22308 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-2023-22308?

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-2023-22308 published?

CVE-2023-22308 was published on 2023-10-12 and last updated on 2026-06-17.

CVE-2023-22308

CVE-2023-22308 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-191.

Key facts

Severity: High (CVSS 3.x base score 7.5)
EPSS exploit prediction: 1% (50th percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-191
Affected product: Softether Vpn
Published: 2023-10-12
Last modified: 2026-06-17

Description

An integer underflow vulnerability exists in the vpnserver OvsProcessData functionality of SoftEther VPN 5.01.9674 and 5.02. A specially crafted network packet can lead to denial of service. An attacker can send a malicious packet to trigger this vulnerability.

Frequently asked questions

What is CVE-2023-22308?: An integer underflow vulnerability exists in the vpnserver OvsProcessData functionality of SoftEther VPN 5.01.9674 and 5.02. A specially crafted network packet can lead to denial of service. An attacker can send a malicious packet to trigger this vulnerability.
How severe is CVE-2023-22308?: CVE-2023-22308 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-2023-22308 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (50th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2023-22308?: CVE-2023-22308 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-2023-22308?: 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-2023-22308 published?: CVE-2023-22308 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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