Nagios XI before v5.8.7 was discovered to contain multiple cross-site scripting (XSS) vulnerabilities at auditlog.php.

Nagios XI v5.8.6 was discovered to contain a cross-site scripting (XSS) vulnerability via the System Settings page under the Admin panel.

In Nagios XI through 5.8.5, an open redirect vulnerability exists in the login function that could lead to spoofing.

In Nagios XI through 5.8.5, a read-only Nagios user (due to an incorrect permission check) is able to schedule downtime for any host/services. This allows an attacker to permanently disable all monitoring checks.

In Nagios XI through 5.8.5, it is possible for a user without password verification to change his e-mail address.

In Nagios XI through 5.8.5, in the schedule report function, an authenticated attacker is able to inject HTML tags that lead to the reformatting/editing of emails from an official email address.

An issue was discovered in Nagios XI 5.8.5. In the Manage Dashlets section of the Admin panel, an administrator can upload ZIP files. A command injection (within the name of the first file in the archive) allows an attacker to execute system commands.

An issue was discovered in Nagios XI 5.8.5. Insecure file permissions on the nagios_unbundler.py file allow the nagios user to elevate their privileges to the root user.

An issue was discovered in Nagios XI 5.8.5. In the Custom Includes section of the Admin panel, an administrator can upload files with arbitrary extensions as long as the MIME type corresponds to an image. Therefore it is possible to upload a crafted PHP script to achieve remote command execution.

The general user interface in Nagios XI versions prior to 5.8.4 is vulnerable to authenticated reflected cross-site scripting. An authenticated victim, who accesses a specially crafted malicious URL, would unknowingly execute the attached payload.