CVE-2021-36749

Apache Druid: The HTTP inputSource allows authenticated users to read data from other sources than intended (incomplete fix of CVE-2021-26920)

Description

In the Druid ingestion system, the InputSource is used for reading data from a certain data source. However, the HTTP InputSource allows authenticated users to read data from other sources than intended, such as the local file system, with the privileges of the Druid server process. This is not an elevation of privilege when users access Druid directly, since Druid also provides the Local InputSource, which allows the same level of access. But it is problematic when users interact with Druid indirectly through an application that allows users to specify the HTTP InputSource, but not the Local InputSource. In this case, users could bypass the application-level restriction by passing a file URL to the HTTP InputSource. This issue was previously mentioned as being fixed in 0.21.0 as per CVE-2021-26920 but was not fixed in 0.21.0 or 0.21.1.

Remediation

Workaround:

  • Users can avoid the issue by upgrading to 0.22.0 or a higher version. In an earlier version than 0.22.0, when the user application wants to restrict the access to the local file system, it should disallow all InputSources that can read local files, that is the Local, HTTP, and HDFS InputSources.

Category

6.5
CVSS
Severity: Medium
CVSS 3.1 •
CVSS 2.0 •
EPSS 93.15% Top 5%
Vendor Advisory apache.org
Affected: Apache Software Foundation Apache Druid
Published at:
Updated at:

References

Frequently Asked Questions

What is the severity of CVE-2021-36749?
CVE-2021-36749 has been scored as a medium severity vulnerability.
How to fix CVE-2021-36749?
As a workaround for remediating CVE-2021-36749: Users can avoid the issue by upgrading to 0.22.0 or a higher version. In an earlier version than 0.22.0, when the user application wants to restrict the access to the local file system, it should disallow all InputSources that can read local files, that is the Local, HTTP, and HDFS InputSources.
Is CVE-2021-36749 being actively exploited in the wild?
It is possible that CVE-2021-36749 is being exploited or will be exploited in a near future based on public information. According to its EPSS score, there is a ~93% probability that this vulnerability will be exploited by malicious actors in the next 30 days.
What software or system is affected by CVE-2021-36749?
CVE-2021-36749 affects Apache Software Foundation Apache Druid.
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