Privilege escalation in Tribe29 Checkmk Appliance before 1.6.4 allows authenticated site users to escalate privileges via incorrectly set permissions.

Inappropriate error handling in Tribe29 Checkmk <= 2.1.0p25, <= 2.0.0p34, <= 2.2.0b3 (beta), and all versions of Checkmk 1.6.0 causes the symmetric encryption of agent data to fail silently and transmit the data in plaintext in certain configurations.

HTML Email Injection in Tribe29 Checkmk <=2.1.0p23; <=2.0.0p34, and all versions of Checkmk 1.6.0 allows an authenticated attacker to inject malicious HTML into Emails

Improper Input Validation of LDAP user IDs in Tribe29 Checkmk allows attackers that can control LDAP user IDs to manipulate files on the server. Checkmk <= 2.1.0p19, Checkmk <= 2.0.0p32, and all versions of Checkmk 1.6.0 (EOL) are affected.

A permission issue affects users that deployed the shipped version of the Checkmk Debian package. Packages created by the agent bakery (enterprise editions only) were not affected. Using the shipped version of the agents, the maintainer scripts located at /var/lib/dpkg/info/ will be owned by the user and the group with ID 1001. If such a user exists on the system, they can change the content of these files (which are then executed by root). This leads to a local privilege escalation on the monitored host. Version 1.6 through 1.6.9p29, version 2.0 through 2.0.0p26, version 2.1 through 2.1.0p3, and version 2.2.0i1 are affected.

In Checkmk before 1.6.0p29, 2.x before 2.0.0p25, and 2.1.x before 2.1.0b10, a site user can escalate to root by editing an OMD hook symlink.

CheckMK Raw Edition software (versions 1.5.0 to 1.6.0) does not sanitise the input of a web service parameter that is in an unauthenticated zone. This Reflected XSS allows an attacker to open a backdoor on the device with HTML content and interpreted by the browser (such as JavaScript or other client-side scripts) or to steal the session cookies of a user who has previously authenticated via a man in the middle. Successful exploitation requires access to the web service resource without authentication.

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