Description
Apache Druid includes the ability to execute user-provided JavaScript code embedded in various types of requests. This functionality is intended for use in high-trust environments, and is disabled by default. However, in Druid 0.20.0 and earlier, it is possible for an authenticated user to send a specially-crafted request that forces Druid to run user-provided JavaScript code for that request, regardless of server configuration. This can be leveraged to execute code on the target machine with the privileges of the Druid server process.
Remediation
References
http://packetstormsecurity.com/files/162345/Apache-Druid-0.20.0-Remote-Command-Execution.html
http://www.openwall.com/lists/oss-security/2021/01/29/6
https://lists.apache.org/thread.html/r04fa1ba93599487c95a8497044d37f8c02a439bfcf92b4567bfb7c8f%40%3Ccommits.druid.apache.org%3E
https://lists.apache.org/thread.html/r121abe8014d381943b63c60615149d40bde9dc1c868bcee90d0d0848%40%3Ccommits.druid.apache.org%3E
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https://lists.apache.org/thread.html/r443e2916c612fbd119839c0fc0729327d6031913a75081adac5b43ad%40%3Cdev.druid.apache.org%3E
https://lists.apache.org/thread.html/r4f84b542417ea46202867c0a8b3eaf3b4cfed30e09174a52122ba210%40%3Ccommits.druid.apache.org%3E
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