{"id":"CVE-2026-58393","aliases":["EUVD-2026-102115","GHSA-2m9v-p7r9-gfcw"],"status":"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/\u003cvpnid\u003e/\u003ccommon_name\u003e 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.","severity":{"version":"3.1","score":5.9,"vector":"CVSS:3.1/AV:N/AC:H/PR:L/UI:N/S:U/C:N/I:H/A:L","level":"medium","assessor":"cna","from":"cve"},"epss":{"day":"2026-11-11","score":0.00433,"percentile":0.38033,"model":"v2026.06.15"},"facts":{"in_kev":false,"known_exploited":false,"public_exploit":false,"fix_available":false},"cwes":["CWE-22"],"published":"2026-10-15T15:15:45Z","modified":"2026-10-28T02:30:30Z","products":[{"vendor":"opnsense","product":"core"}],"references":[{"url":"https://github.com/opnsense/core/security/advisories/GHSA-2m9v-p7r9-gfcw","tags":["x_refsource_CONFIRM","exploit","advisory"]},{"url":"https://github.com/opnsense/core/commit/3af496143a19153c18b2f9458b2510d58aff2b98","tags":["x_refsource_MISC","fix"]},{"url":"https://github.com/opnsense/core/commit/6101b3e2c90482111f420a47775c14a447441a72","tags":["x_refsource_MISC","fix"]},{"url":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/58xxx/CVE-2026-58393.json","tags":["advisory"]},{"url":"https://nvd.nist.gov/vuln/detail/CVE-2026-58393","tags":["advisory"]}],"sources":{"cve":[{"id":"CVE-2026-58393","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/\u003cvpnid\u003e/\u003ccommon_name\u003e 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.","status":"published","published":"2026-10-15T15:15:45.924Z","modified":"2026-10-15T16:07:55.688Z","cvss":[{"version":"3.1","score":5.9,"vector":"CVSS:3.1/AV:N/AC:H/PR:L/UI:N/S:U/C:N/I:H/A:L","level":"medium","assessor":"cna"}],"cwes":["CWE-22"],"updated_at":"2026-11-02T13:47:28.691429Z"}],"euvd":[{"id":"EUVD-2026-102115","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/\u003cvpnid\u003e/\u003ccommon_name\u003e 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.","status":"published","published":"2026-10-15T15:15:45Z","modified":"2026-10-15T16:07:55Z","cvss":[{"version":"3.1","score":5.9,"vector":"CVSS:3.1/AV:N/AC:H/PR:L/UI:N/S:U/C:N/I:H/A:L","level":"medium"}],"updated_at":"2026-11-02T17:00:12.42385Z"}],"nvd":[{"id":"CVE-2026-58393","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/\u003cvpnid\u003e/\u003ccommon_name\u003e 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.","status":"published","published":"2026-10-15T16:18:18.31Z","modified":"2026-10-15T21:08:49.703Z","cvss":[{"version":"3.1","score":5.9,"vector":"CVSS:3.1/AV:N/AC:H/PR:L/UI:N/S:U/C:N/I:H/A:L","level":"medium","assessor":"secondary"}],"cwes":["CWE-22"],"updated_at":"2026-11-02T14:12:59.751798Z"}],"osv":[{"id":"CVE-2026-58393","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/\u003cvpnid\u003e/\u003ccommon_name\u003e 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.","status":"published","published":"2026-10-15T15:15:45.924Z","modified":"2026-10-28T02:30:30.726824989Z","cvss":[{"version":"3.1","score":5.9,"vector":"CVSS:3.1/AV:N/AC:H/PR:L/UI:N/S:U/C:N/I:H/A:L","level":"medium"}],"cwes":["CWE-22"],"updated_at":"2026-11-02T15:45:12.496548Z"}]}}