Werk #16172: kaspersky_av: Don't run kav4fs-control or kesl-control if they aren't owned by root

Component Checks & agents
Title kaspersky_av: Don't run kav4fs-control or kesl-control if they aren't owned by root
Date Feb 27, 2024
Level Trivial Change
Class Security Fix
Compatibility Compatible - no manual interaction needed
Checkmk versions & editions
2.4.0b1
Not yet released
Checkmk Raw (CRE), Checkmk Enterprise (CEE), Checkmk Cloud (CCE), Checkmk MSP (CME)
2.3.0b1 Checkmk Raw (CRE), Checkmk Enterprise (CEE), Checkmk Cloud (CCE), Checkmk MSP (CME)
2.2.0p24 Checkmk Raw (CRE), Checkmk Enterprise (CEE), Checkmk Cloud (CCE), Checkmk MSP (CME)

Kaspersky Anti-Virus plugin uses /opt/kaspersky/kav4fs/bin/kav4fs-control and /opt/kaspersky/kesl/bin/kesl-control commands to monitor a Kaspersky Anti-Virus installation.

To prevent privilege escalation, the plugin (which is run by root user) must not run executables which can be changed by less privileged users.

In the default installation, kav4fs-control and kesl-control commands are owned by root and root is the only user with write permissions, which prevents privilege escalation attacks.

With this Werk, the plugin checks if control commands are owned by root and root is the only user with write permissions before running the command. If that's not the case the commands won't be run. This prevents privilege escalation attacks if the permissions of the control commands have been changed.

We rate this with a CVSS of 0 (None) (CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:N). This CVSS is primarily meant to please automatic scanners.

To the list of all Werks