EN

CVE-2026-41070

Critical
10.0
0.05.010.0
Year
2026
Published
May 8, 2026
Known Affected Devices
0
CVSS Score
10.0

What is CVE-2026-41070?

openvpn-auth-oauth2 is a plugin/management interface client for OpenVPN server to handle an OIDC based single sign-on (SSO) auth flows. From version 1.26.3 to before version 1.27.3, when openvpn-auth-oauth2 is deployed in the experimental plugin mode (shared library loaded by OpenVPN via the plugin directive), clients that do not support WebAuth/SSO (e.g., the openvpn CLI on Linux) are incorrectly admitted to the VPN despite being denied by the authentication logic. The default management-interface mode is not affected because it does not use the OpenVPN plugin return-code mechanism. This issue has been patched in version 1.27.3.

CVSS Vector Breakdown

CVSS 3.1
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:H/I:H/A:N
AV
Attack Vector
Network

Exploitable remotely over the network without requiring access to the local system.

AC
Attack Complexity
Low

No special conditions required. Exploit can be performed reliably and repeatedly.

PR
Privileges Required
None

No authentication required. Any anonymous user can exploit this vulnerability.

UI
User Interaction
None

No user interaction required. Exploit runs without any victim action.

S
Scope
Changed

Exploiting the vulnerability can affect other components beyond the vulnerable one.

C
Confidentiality Impact
High

Complete loss of confidentiality. All data on the component may be exposed.

I
Integrity Impact
High

Complete loss of integrity. Attacker can modify any file or data on the component.

A
Availability Impact
None

No availability impact. Service remains fully operational.

FAQ

How severe is CVE-2026-41070?

CVE-2026-41070 has a CVSS score of 10.0/10, rated as Critical. This is the highest severity level - immediate patching is strongly recommended.

What does the CVSS score mean for CVE-2026-41070?

CVSS (Common Vulnerability Scoring System) rates vulnerability severity from 0.0 to 10.0. CVE-2026-41070 scores 10.0/10 (Critical). Scores 9.0–10.0 are Critical, 7.0–8.9 are High, 4.0–6.9 are Medium, and below 4.0 are Low.

Which devices are affected by CVE-2026-41070?

The list of devices confirmed to be affected by CVE-2026-41070 is shown in the "Affected Devices" section above. Check your firmware version against the vendor security advisory and apply the latest patch.

How do I fix or mitigate CVE-2026-41070?

Apply the latest firmware or software update from the vendor. Check the References section above for official advisories and patch notes. If no patch is available, consider disabling the affected feature or isolating the device from untrusted networks.