CVE-2025-13086

Severity: high (CVSS 7.5 v3.1)
Exploited in the wild: not listed in CISA KEV
EPSS: 0.6% probability of exploitation in the next 30 days
Public exploit or detection template: none known
Published: 2025-12-03 · updated 2026-09-25
Weakness: CWE-940

Description

Improper validation of source IP addresses in OpenVPN version 2.6.0 through 2.6.15 and 2.7_alpha1 through 2.7_rc1 allows an attacker to open a session from a different IP address which did not initiate the connection resulting in a denial of service for the originating client

Affected products

OpenVPN: from 2.6.0 before 2.6.16; 2.7-alpha1, 2.7-alpha2, 2.7-alpha3, 2.7-beta1, 2.7-beta2, 2.7-beta3 (+1) — fixed in 2.6.16

How to fix

Upgrade to a fixed version: OpenVPN 2.6.16. Check the vendor advisory for mitigations.

References

https://community.openvpn.net/Security%20Announcements/CVE-2025-13086
https://www.mail-archive.com/openvpn-announce@lists.sourceforge.net/msg00151.html
https://www.mail-archive.com/openvpn-announce@lists.sourceforge.net/msg00152.html

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