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)
- Published
- Sep 24, 2021
- Updated
- Aug 4, 2024
- Assigning CNA
- apache
- Evidence observed
- Aug 8, 2026
Primary CVSS
nvd · CVSS 3.1
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:N/A:NHigh · next 30 days
- Percentile
- 99.6%
- Model date
- Sep 21, 2026
EPSS is a statistical estimate, not a certainty or a measure of impact. Combine it with CVSS, KEV status, exposure and your environment.
Summary
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.
Sources
5Proof-of-concept exploit for CVE-2021-36749, demonstrating SSRF via Druid's HTTP InputSource to read local files. Useful for security testing and vulnerability validation.
Apache Druid 任意文件读取
Responsible use
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