GHSA-h475-7v3c-26q7: Command injection in OpenTSDB

This Metasploit module exploits an unauthenticated command injection vulnerability in the key parameter in OpenTSDB through 2.4.1 in order to achieve unauthenticated remote code execution as the root user. The module first attempts to obtain the OpenTSDB version via the api. If the version is 2.4.1 or lower, the module performs additional checks to obtain the configured metrics and aggregators. It then randomly selects one metric and one aggregator and uses those to instruct the target server to plot a graph. As part of this request, the key parameter is set to the payload, which will then be executed by the target if the latter is vulnerable. This module has been successfully tested against OpenTSDB version 2.4.1.

Due to insufficient validation of parameters passed to the legacy HTTP query API, it is possible to inject crafted OS commands into multiple parameters and execute malicious code on the OpenTSDB host system. This exploit exists due to an incomplete fix that was made when this vulnerability was previously disclosed as CVE-2020-35476. Regex validation that was implemented to restrict allowed input to the query API does not work as intended, allowing crafted commands to bypass validation.