CVE-2026-39312
High
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.
SeverityHigh
CVSS7.5
Exploit probability41. percentile0.5%
ProductSoftethervpn
PublishedApr 7, 2026
First seenApr 7, 2026
Weakness typeCWE-789CWE-789
How to fix
Sources list no fixed version or patch link for this vulnerability.
Affected products
| Product | Affected versions | Fixed in |
|---|---|---|
| softether softethervpn | v ≤ 5.2.5188 | — |
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