How severe is CVE-2023-27395?

CVE-2023-27395 has a CVSS 3.x base score of 9.0, rated critical severity. It is exploitable over network with high attack complexity, requires no privileges and no user interaction. Impact on confidentiality is high, integrity high, and availability high.

Is CVE-2023-27395 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 2% (72nd percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2023-27395?

CVE-2023-27395 primarily affects Softether Vpn. In total, 3 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.

How do I fix CVE-2023-27395?

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

When was CVE-2023-27395 published?

CVE-2023-27395 was published on 2023-10-12 and last updated on 2026-06-17.

CVE-2023-27395

CVE-2023-27395 is a critical-severity vulnerability in Softether Vpn with a CVSS 3.x base score of 9.0. 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-787.

Key facts

Severity: Critical (CVSS 3.x base score 9.0)
EPSS exploit prediction: 2% (72nd percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-787
Affected product: Softether Vpn
Published: 2023-10-12
Last modified: 2026-06-17

Description

A heap-based buffer overflow vulnerability exists in the vpnserver WpcParsePacket() functionality of SoftEther VPN 4.41-9782-beta, 5.01.9674 and 5.02. A specially crafted network packet can lead to arbitrary code execution. An attacker can perform a man-in-the-middle attack to trigger this vulnerability.

Frequently asked questions

What is CVE-2023-27395?: A heap-based buffer overflow vulnerability exists in the vpnserver WpcParsePacket() functionality of SoftEther VPN 4.41-9782-beta, 5.01.9674 and 5.02. A specially crafted network packet can lead to arbitrary code execution. An attacker can perform a man-in-the-middle attack to trigger this vulnerability.
How severe is CVE-2023-27395?: CVE-2023-27395 has a CVSS 3.x base score of 9.0, rated critical severity. It is exploitable over network with high attack complexity, requires no privileges and no user interaction. Impact on confidentiality is high, integrity high, and availability high.
Is CVE-2023-27395 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 2% (72nd percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2023-27395?: CVE-2023-27395 primarily affects Softether Vpn. In total, 3 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.
How do I fix CVE-2023-27395?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its critical severity, prioritise patching exposed systems.
When was CVE-2023-27395 published?: CVE-2023-27395 was published on 2023-10-12 and last updated on 2026-06-17.

References

Affected products (3)

cpe:2.3:a:softether:vpn:4.41-9782:beta:*:*:*:*:*:*
cpe:2.3:a:softether:vpn:5.01.9674:*:*:*:*:*:*:*
cpe:2.3:a:softether:vpn:5.02:*:*:*:*:*:*:*

More vulnerabilities in Softether Vpn

CVE-2025-25568 — Critical (CVSS 9.8): SoftEtherVPN 5.02.5187 is vulnerable to Use after Free in the Command.c file via the CheckNetworkAcceptThread function.…
CVE-2025-25567 — Critical (CVSS 9.8): SoftEther VPN 5.02.5187 is vulnerable to Buffer Overflow in Internat.c via the UniToStrForSingleChars function. NOTE:…
CVE-2025-25565 — Critical (CVSS 9.8): SoftEther VPN 5.02.5187 is vulnerable to Buffer Overflow in the Command.c file via the PtMakeCert and PtMakeCert2048…
CVE-2023-32634 — High (CVSS 7.8): An authentication bypass vulnerability exists in the CiRpcServerThread() functionality of SoftEther VPN 5.01.9674 and…
CVE-2023-25774 — High (CVSS 7.5): A denial-of-service vulnerability exists in the vpnserver ConnectionAccept() functionality of SoftEther VPN 5.02. A set…
CVE-2023-23581 — High (CVSS 7.5): A denial-of-service vulnerability exists in the vpnserver EnSafeHttpHeaderValueStr functionality of SoftEther VPN…

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