CVE-2026-84194

LibreNMS before version 26.8.0 contains an authentication bypass vulnerability in the REST API that allows unauthenticated attackers to access protected endpoints by sending numeric values instead of string tokens. Attackers can exploit MySQL type coercion by sending small integers like 0 through 9 to match token hashes, gaining access to API functionality including device credentials and administrative features that enable remote code execution through alert templates.

LibreNMS before 24.10.0 allows a remote attacker to execute arbitrary code via OS command injection involving AboutController.php's index(), SettingsController.php's update(), and PollDevice.php's initRrdDirectory().

LibreNMS prior to version 25.12.0 is vulnerable to stored cross-site scripting in the Alert Rule API. Alert rules can be created or updated via the LibreNMS API, and the alert rule name is not properly sanitized, allowing HTML code injection. This issue has been patched in version 25.12.0.

LibreNMS prior to version 25.11.0 contains a boolean-based blind SQL injection vulnerability at the /ajax_output.php endpoint. The hostname parameter is interpolated directly into an SQL query without proper sanitization or parameter binding, allowing an attacker to manipulate the query logic and infer data from the database through conditional responses. This issue has been patched in version 25.11.0.

LibreNMS <= 25.8.0 contains a Stored Cross-Site Scripting (XSS) vulnerability in the Alert Transports management functionality. The Transport name field value is stored and later rendered in the Transports column of the Alert Rules page without proper input validation or output encoding, leading to arbitrary JavaScript execution in the admin's browser. This vulnerability is fixed in 25.10.0.

LibreNMS before 26.9.0 contains an LDAP filter injection in ldap-authorization and ad-authorization modes because usernames are inserted unescaped into LDAP search filters and authentication only checks user existence. When REMOTE_USER is not forwarded, unauthenticated attackers can send a wildcard username via HTTP Basic Authorization (PHP_AUTH_USER) to match all users and groups and gain admin access.

LibreNMS before 26.9.0 contains a missing authorization vulnerability in PortsController::purge that allows global-read users to physically delete ports without delete privileges. Attackers with read-only accounts can send DELETE requests to /ports/purge, using purge=all to irreversibly erase every deleted port on all visible devices.

LibreNMS before 26.9.0 contains a stored cross-site scripting vulnerability in get_oxidized_nodes_list() that renders Oxidized API fields and SNMP sysName unescaped. Attackers controlling the Oxidized response or a device's SNMP sysName can inject script that executes in browsers of users viewing the Tools Oxidized page.

LibreNMS before 26.9.0 contains a path traversal vulnerability in nfsen_channel_common.inc.php that allows authenticated users to read unauthorized RRD data by injecting ../ sequences into the channel parameter. Attackers with access to one NFSen-enabled device can request graph.php with a traversed channel value to view traffic and NetFlow graphs of devices outside their authorized scope.

LibreNMS before 26.9.0 contains an SQL injection vulnerability that allows unprivileged users to inject SQL by supplying an array-valued notification_id parameter to notifications.inc.php. Attackers can perform cross-table reads of users.password hashes, with results persisted in notifications_attribs and readable through the interface.