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Vulnerability record · CVE-2021-26920 · published 2 July 2021

CVE-2021-26920: Apache druid vulnerability

Apache · Druid

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.

6.5 CVSS 3.1 Medium EPSS 9.5% · top 4.7% CWE-610 · CWE-610
6.5CVSS 3.1 base score, v2 4.0
9.5%EPSS exploitation probability, 30 days
NoNot in CISA KEV
1Affected product versions listed by NVD
12References
17 Jun 2026Last modified by NVD

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.

CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:N/A:N

Affected products

1 vulnerable configurations from NVD's CPE data, grouped by vendor and product.

References

LinkTags
http://www.openwall.com/lists/oss-security/2021/07/02/1 Mailing ListThird Party Advisory
http://www.openwall.com/lists/oss-security/2021/09/24/1 Mailing ListThird Party Advisory
https://lists.apache.org/thread.html/r29e45561343cc5cf7d3290ee0b0e94e565faab19c20d022df9b5e29c%40%3Cdev.druid.apache.org Mailing ListVendor Advisory
https://lists.apache.org/thread.html/r304dfe56a5dfe1b2d9166b24d2c74ad1c6730338b20aef77a00ed2be%40%3Cannounce.apache.org%
https://lists.apache.org/thread.html/r61aab724cf97d80da7f02d50e9af6de5c7c40dd92dab7518746fbaa2%40%3Cannounce.apache.org%
https://lists.apache.org/thread.html/rc9400a70d0ec5cdb8a3486fc5ddb0b5282961c0b63e764abfbcb9f5d%40%3Cdev.druid.apache.org
http://www.openwall.com/lists/oss-security/2021/07/02/1 Mailing ListThird Party Advisory
http://www.openwall.com/lists/oss-security/2021/09/24/1 Mailing ListThird Party Advisory
https://lists.apache.org/thread.html/r29e45561343cc5cf7d3290ee0b0e94e565faab19c20d022df9b5e29c%40%3Cdev.druid.apache.org Mailing ListVendor Advisory
https://lists.apache.org/thread.html/r304dfe56a5dfe1b2d9166b24d2c74ad1c6730338b20aef77a00ed2be%40%3Cannounce.apache.org%
https://lists.apache.org/thread.html/r61aab724cf97d80da7f02d50e9af6de5c7c40dd92dab7518746fbaa2%40%3Cannounce.apache.org%
https://lists.apache.org/thread.html/rc9400a70d0ec5cdb8a3486fc5ddb0b5282961c0b63e764abfbcb9f5d%40%3Cdev.druid.apache.org

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Related vulnerabilities

Same products first, then exploited flaws of the same weakness class.

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Source: NIST National Vulnerability Database (record CVE-2021-26920), CISA KEV, FIRST EPSS (scores of 2026-09-26). This page is refreshed as NVD updates the record.