{"id":"CVE-2026-58393","state":"PUBLISHED","title":"OPNsense: OpenVPN Client Specific Override common_name allows path traversal in generated CSO files","description":"OPNsense is a FreeBSD based firewall and routing platform. Prior to version 26.1.11, the OpenVPN Client Specific Override common_name field accepts path traversal sequences and openvpn_csc_conf_write() concatenates the value into /var/etc/openvpn-csc/<vpnid>/<common_name> without normalization or a basename check. The affected event handlers are client_connect.php and user_pass_verify.php. An authenticated user with Client Specific Override privileges can store the traversal value, and a matching OpenVPN client-connect or authentication event causes a generated CSO file to be written outside the intended directory. The file content is generated OpenVPN configuration rather than arbitrary bytes, and practical exploitation requires the attacker to cause a matching common name or username to be processed. This issue is fixed in version 26.1.11.","publishedAt":"2026-10-15T15:15:45.924Z","updatedAt":"2026-10-15T16:07:55.688Z","severity":{"score":5.9,"label":"Medium","version":"3.1","vector":"CVSS:3.1/AV:N/AC:H/PR:L/UI:N/S:U/C:N/I:H/A:L","source":"GitHub_M"},"assigner":"GitHub_M","products":["opnsense core"],"affected":[{"vendor":"opnsense","product":"core","versions":[{"version":"< 26.1.11","status":"affected"}]}],"references":["https://github.com/opnsense/core/security/advisories/GHSA-2m9v-p7r9-gfcw","https://github.com/opnsense/core/commit/3af496143a19153c18b2f9458b2510d58aff2b98","https://github.com/opnsense/core/commit/6101b3e2c90482111f420a47775c14a447441a72"],"weaknesses":["CWE-22"],"ingestedAt":"2026-10-29T20:12:24.861Z","source":{"repository":"CVEProject/cvelistV5","path":"cves/2026/58xxx/CVE-2026-58393.json","commit":"556c9d3a8cd17e218bb8e452ba7cd619a384ff47"},"raw":{"dataType":"CVE_RECORD","dataVersion":"5.2","cveMetadata":{"cveId":"CVE-2026-58393","state":"PUBLISHED","datePublished":"2026-10-15T15:15:45.924Z","dateUpdated":"2026-10-15T16:07:55.688Z","assignerShortName":"GitHub_M","assignerOrgId":"a0819718-46f1-4df5-94e2-005712e83aaa","dateReserved":"2026-06-30T18:19:58.377Z"},"containers":{"cna":{"title":"OPNsense: OpenVPN Client Specific Override common_name allows path traversal in generated CSO files","descriptions":[{"lang":"en","value":"OPNsense is a FreeBSD based firewall and routing platform. Prior to version 26.1.11, the OpenVPN Client Specific Override common_name field accepts path traversal sequences and openvpn_csc_conf_write() concatenates the value into /var/etc/openvpn-csc/<vpnid>/<common_name> without normalization or a basename check. The affected event handlers are client_connect.php and user_pass_verify.php. An authenticated user with Client Specific Override privileges can store the traversal value, and a matching OpenVPN client-connect or authentication event causes a generated CSO file to be written outside the intended directory. The file content is generated OpenVPN configuration rather than arbitrary bytes, and practical exploitation requires the attacker to cause a matching common name or username to be processed. This issue is fixed in version 26.1.11."}],"affected":[{"vendor":"opnsense","product":"core","versions":[{"version":"< 26.1.11","status":"affected"}]}],"references":[{"url":"https://github.com/opnsense/core/security/advisories/GHSA-2m9v-p7r9-gfcw","name":"https://github.com/opnsense/core/security/advisories/GHSA-2m9v-p7r9-gfcw","tags":["x_refsource_CONFIRM"]},{"url":"https://github.com/opnsense/core/commit/3af496143a19153c18b2f9458b2510d58aff2b98","name":"https://github.com/opnsense/core/commit/3af496143a19153c18b2f9458b2510d58aff2b98","tags":["x_refsource_MISC"]},{"url":"https://github.com/opnsense/core/commit/6101b3e2c90482111f420a47775c14a447441a72","name":"https://github.com/opnsense/core/commit/6101b3e2c90482111f420a47775c14a447441a72","tags":["x_refsource_MISC"]}],"metrics":[{"cvssV3_1":{"attackComplexity":"HIGH","attackVector":"NETWORK","availabilityImpact":"LOW","baseScore":5.9,"baseSeverity":"MEDIUM","confidentialityImpact":"NONE","integrityImpact":"HIGH","privilegesRequired":"LOW","scope":"UNCHANGED","userInteraction":"NONE","vectorString":"CVSS:3.1/AV:N/AC:H/PR:L/UI:N/S:U/C:N/I:H/A:L","version":"3.1"}}],"problemTypes":[{"descriptions":[{"cweId":"CWE-22","lang":"en","description":"CWE-22: Improper Limitation of a Pathname to a Restricted Directory ('Path Traversal')","type":"CWE"}]}],"providerMetadata":{"shortName":"GitHub_M","orgId":"a0819718-46f1-4df5-94e2-005712e83aaa","dateUpdated":"2026-10-15T15:15:45.924Z"},"source":{"advisory":"GHSA-2m9v-p7r9-gfcw","discovery":"UNKNOWN"}},"adp":[{"title":"CISA ADP Vulnrichment","references":[{"url":"https://github.com/opnsense/core/security/advisories/GHSA-2m9v-p7r9-gfcw","tags":["exploit"]}],"metrics":[{"other":{"type":"ssvc","content":{"timestamp":"2026-10-15T16:07:43.427308Z","id":"CVE-2026-58393","options":[{"Exploitation":"poc"},{"Automatable":"no"},{"Technical Impact":"partial"}],"role":"CISA Coordinator","version":"2.0.3"}}}],"providerMetadata":{"shortName":"CISA-ADP","orgId":"134c704f-9b21-4f2e-91b3-4a467353bcc0","dateUpdated":"2026-10-15T16:07:55.688Z"}}]}}}