CVE-2026-39312

Name: CVE-2026-39312
Creator: NVD / NIST
Published: 2026-04-07T17:16:36.92+00:00
License: https://creativecommons.org/publicdomain/zero/1.0/

HIGHCVSS 7.5/10EPSS 0.45%

Last modified Jun 17, 2026

CVE-2026-39312 is a high-severity vulnerability rated 7.5/10 on the CVSS scale. SoftEtherVPN is a an open-source cross-platform multi-protocol VPN Program. In 5.2.5188 and earlier, a pre-authentication denial-of-service vulnerability exists in SoftEther VPN Developer Edition 5.2.5188 (and likely earlier versions of Developer Edition). EPSS estimates a 0.45% chance of exploitation in the next 30 days.

Description

SoftEtherVPN is a an open-source cross-platform multi-protocol VPN Program. In 5.2.5188 and earlier, a pre-authentication denial-of-service vulnerability exists in SoftEther VPN Developer Edition 5.2.5188 (and likely earlier versions of Developer Edition). An unauthenticated remote attacker can crash the vpnserver process by sending a single malformed EAP-TLS packet over raw L2TP (UDP/1701), terminating all active VPN sessions.

Metrics

CVSS 3.1

7.5/10

CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H

EPSS Probability

0.45%

35.9th percentile

Probability of exploitation in the next 30 days. Learn more

Weakness Enumeration

CWE-789

Affected Software

Vendor	Product	Versions
Softether	Softethervpn	<= 5.2.5188

References

https://github.com/SoftEtherVPN/SoftEtherVPN/security/advisories/GHSA-q5g3-qhc6-pr3hExploit, Mitigation, Vendor Advisory
https://github.com/SoftEtherVPN/SoftEtherVPN/security/advisories/GHSA-q5g3-qhc6-pr3hExploit, Mitigation, Vendor Advisory

Timeline

Published: Apr 7, 2026
Last Modified: Jun 17, 2026
Status: Analyzed

Frequently Asked Questions

What is CVE-2026-39312?

How severe is CVE-2026-39312?

CVE-2026-39312 has a CVSS score of 7.5/10 (HIGH severity). The EPSS model estimates a 0.45% probability of exploitation in the next 30 days.

How do I fix CVE-2026-39312?

Check the vendor references and advisories linked above for patched versions and mitigation guidance. You can also run a Strix scan to test if your systems are affected.

Are you affected by CVE-2026-39312?

Run a free Strix scan to check your systems for this vulnerability.

Scan your code now

Source: NVD / NIST