The web management console of CheckMK Enterprise Edition (versions 1.5.0 to 2.0.0p9) does not properly sanitise the uploading of ".mkp" files, which are Extension Packages, making remote code execution possible. Successful exploitation requires access to the web management interface, either with valid credentials or with a hijacked session of a user with administrator role. NOTE: the vendor states that this is the intended behavior: admins are supposed to be able to execute code in this manner.

User Messages widget leaked issuer messages on shared dashboards

Incorrect authorization in the User Messages dashboard widget in Checkmk <2.5.0p5 causes the message-fetching endpoints to return the dashboard creator's messages rather than the viewer's, allowing an attacker who knows a valid public dashboard share token to read the issuer's personal messages by sending requests to the underlying endpoint, even without a User Messages widget present.

XSS in urls

Improper neutralization of HTML-encoded characters in the URL validation function in Checkmk <2.5.0p5, <2.4.0p31, <2.3.0p48, and all 2.2.0 versions allows an authenticated user to bypass URL validation and inject malicious URLs such as javascript: URIs, resulting in cross-site scripting when another user interacts with the crafted link.

Fix stored XSS in global settings change log

Stored cross-site scripting in the global settings change log in Checkmk <2.5.0p5, <2.4.0p31, <2.3.0p48, and all 2.2.0 versions allows an administrator who can change global settings to store malicious HTML or JavaScript in changelog messages that executes in other users' browsers when they view the Activate Changes page or Audit log.

Fix stored XSS in URL dashboard widget via dangerous URI schemes

Stored cross-site scripting in the URL dashboard widget in Checkmk <2.5.0p5, <2.4.0p31, <2.3.0p48, and all 2.2.0 versions allows a user with dashboard editing permissions to store a URL with a dangerous URI scheme such as javascript: that executes scripts in other users' browsers when they view the dashboard.

Fix XSS in service discovery active check output

Stored cross-site scripting in the service discovery active check output in Checkmk <2.5.0p5, <2.4.0p31, <2.3.0p48, and all 2.2.0 versions allows an administrator who can configure active or custom checks to inject malicious HTML or JavaScript into check output that executes in the browser of an admin or a user with host read permissions when they run the check on the service discovery page.

Privilege escalation via mk_mysql agent plugin on Windows

Privilege escalation in the mk_mysql agent plugin on Windows in Checkmk <2.4.0p29, <2.3.0p47, and 2.2.0 (EOL) allows a local unprivileged user able to create a Windows service whose name matches 'MySQL' or 'MariaDB' (or with write access to a binary referenced by such a service) to execute arbitrary code in the context of the Checkmk agent service, which typically runs as SYSTEM.

Session hijacking via exposed session signing secret in distributed Checkmk setups

Exposure of session signing secret in Checkmk <2.4.0p23, <2.3.0p45 and 2.2.0 allows an administrator of a remote site with config sync enabled to hijack sessions on the central site by forging session cookies.

Cross-site scripting in dashlet title

Insufficient sanitization of dashboard dashlet title links in Checkmk 2.2.0 (EOL), Checkmk 2.3.0 before 2.3.0p46, Checkmk 2.4.0 before 2.4.0p25, and Checkmk 2.5.0 (beta) before 2.5.0 allows an attacker with dashboard creation privileges to perform stored cross-site scripting (XSS) attacks by tricking a victim into clicking a crafted dashlet title link on a shared dashboard.

Livestatus injection in monitoring quicksearch

Livestatus injection in the monitoring quicksearch in Checkmk <2.5.0b4 allows an authenticated attacker to inject livestatus commands via the search query due to insufficient input sanitization in search filter plugins.

Potential livestatus injection in notification test

Livestatus injection in the notification test mode in Checkmk <2.5.0b4 and <2.4.0p26 allows an authenticated user with access to the notification test page to inject arbitrary Livestatus commands via a crafted service description.

Potential livestatus injection in prediction graph page

Livestatus injection in the prediction graph page in Checkmk <2.5.0b4, <2.4.0p26, and <2.3.0p47 allows an authenticated user to inject arbitrary Livestatus commands via a crafted service name parameter due to insufficient sanitization of the service description value.

Cross-site scripting in HTML logs of Synthetic Monitoring test services

Improper neutralization of input in Checkmk versions 2.4.0 before 2.4.0p22, and 2.3.0 before 2.3.0p43 allows an attacker that can manipulate a host's check output to inject malicious JavaScript into the Synthetic Monitoring HTML logs, which can then be accessed via a crafted phishing link.

Missing Permission Check on Analyze Configuration Page

Improper permission enforcement in Checkmk versions 2.4.0 before 2.4.0p21, 2.3.0 before 2.3.0p43, and 2.2.0 (EOL) allows users with the "Use WATO" permission to access the "Analyze configuration" page by directly navigating to its URL, bypassing the intended "Access analyze configuration" permission check. If these users also have the "Make changes, perform actions" permission, they can perform unauthorized actions such as disabling checks or acknowledging results.

Deletion of passwords via RestApi

A logic error in the remove_password() function in Checkmk GmbH's Checkmk versions <2.4.0p23, <2.3.0p43, and 2.2.0 (EOL) allows a low-privileged user to cause data loss.

omd: Local privilege escalation when executing omd commands as root

Local privilege escalation in Checkmk 2.2.0 (EOL), Checkmk 2.3.0 before 2.3.0p46, Checkmk 2.4.0 before 2.4.0p25, and Checkmk 2.5.0 (beta) before 2.5.0b3 allows a site user to escalate their privileges to root, by manipulating files in the site context that are processed when the `omd` administrative command is run by root.

Insufficient permission validation on multiple REST API Quick Setup endpoints

Insufficient permission validation on multiple REST API Quick Setup endpoints in Checkmk 2.5.0 (beta) before version 2.5.0b2 and 2.4.0 before version 2.4.0p25 allows low-privileged users to perform unauthorized actions or obtain sensitive information

XSS in Unified Search via Unescaped Host/Service Names

Stored cross-site scripting (XSS) in Checkmk 2.5.0 (beta) before 2.5.0b2 allows authenticated users with permission to create hosts or services to execute arbitrary JavaScript in the browsers of other users performing searches in the Unified Search feature.

Stored cross-site scripting in Pending Changes sidebar

Stored cross-site scripting (XSS) in Checkmk version 2.5.0 (beta) before 2.5.0b2 allows authenticated users with permission to create pending changes to inject malicious JavaScript into the Pending Changes sidebar, which will execute in the browsers of other users viewing the sidebar.

Authenticated Host Enumeration via Observable Response Discrepancy on Agent Register Existing Endpoint

Improper permission enforcement in Checkmk versions 2.4.0 before 2.4.0p23, 2.3.0 before 2.3.0p43, and 2.2.0 (EOL) allows authenticated users to enumerate existing hosts by observing different HTTP response codes in agent-receiver/register_existing endpoint, which could lead to information disclosure.