Kibana versions before 5.6.15 and 6.6.1 contain an arbitrary code execution flaw in the Timelion visualizer. An attacker with access to the Timelion application could send a request that will attempt to execute javascript code. This leads to an arbitrary command execution with permissions of the Kibana process on the host system. Exploitation will require a service or system reboot to restore normal operation. The WFSDELAY parameter is crucial for this exploit. Setting it too high will cause MANY shells (50-100+), while setting it too low will cause no shells to be obtained. WFSDELAY of 10 for a docker image caused 6 shells.
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