{"id":"CVE-2026-41070","summary":"openvpn-auth-oauth2 returns FUNC_SUCCESS on client-deny, allowing unauthenticated VPN access","details":"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.","aliases":["GHSA-246w-jgmq-88fg","GO-2026-4963"],"modified":"2026-07-08T08:13:20.322070601Z","published":"2026-05-08T15:14:46.186Z","database_specific":{"cwe_ids":["CWE-287"],"cna_assigner":"GitHub_M","osv_generated_from":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/41xxx/CVE-2026-41070.json"},"references":[{"type":"ADVISORY","url":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/41xxx/CVE-2026-41070.json"},{"type":"ADVISORY","url":"https://github.com/jkroepke/openvpn-auth-oauth2/security/advisories/GHSA-246w-jgmq-88fg"},{"type":"ADVISORY","url":"https://nvd.nist.gov/vuln/detail/CVE-2026-41070"},{"type":"FIX","url":"https://github.com/jkroepke/openvpn-auth-oauth2/commit/36f69a6c67c1054da7cbfa04ced3f0555127c8f2"}],"affected":[{"ranges":[{"type":"GIT","repo":"https://github.com/jkroepke/openvpn-auth-oauth2","events":[{"introduced":"24b3bc728995a59dde29c8e02bb1f74b31318f09"},{"fixed":"4d6b317632a89dcfdfa727e83348f1fcd98002e0"}],"database_specific":{"source":"AFFECTED_FIELD","extracted_events":[{"introduced":"1.26.3"},{"fixed":"1.27.3"}]}}],"versions":["v1.27.2","v1.27.1","v1.27.0","v1.26.4","v1.26.3"],"database_specific":{"source":"https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2026-41070.json"}}],"schema_version":"1.7.5","severity":[{"type":"CVSS_V3","score":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:H/I:H/A:N"}]}