Vulnerability in Apache Druid
CVE-2021-26920
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.
Published · last modified .
CVSS v3 metric
CVSS v3 base score 6.5 (Medium). Vector: CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:N/A:N.
EPSS exploit prediction
EPSS: 0.095 (95.3th percentile), scored .
Low probability of exploitation in the next 30 days, but still tracked. 95th percentile — 95.3% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.
EPSS over last 30 days · oldest: 0.099 · newest: 0.095 · change: -0.004
Affected products
- Apache Druid
- Apache Software Foundation Druid — versions Apache Druid
Weakness classification (CWE)
Public proof-of-concept exploits
References
- lists.apache.org/thread.html/r29e45561343cc5cf7d3290ee0b0e94e565faab19c20d022df… (Mailing List, Vendor Advisory)
- www.openwall.com/lists/oss-security/2021/07/02/1 (mailing-list, Mailing List, Third Party Advisory)
- lists.apache.org/thread.html/r61aab724cf97d80da7f02d50e9af6de5c7c40dd92dab75187… (mailing-list)
- lists.apache.org/thread.html/rc9400a70d0ec5cdb8a3486fc5ddb0b5282961c0b63e764abf… (mailing-list)
- www.openwall.com/lists/oss-security/2021/09/24/1 (mailing-list, Mailing List, Third Party Advisory)
- lists.apache.org/thread.html/r304dfe56a5dfe1b2d9166b24d2c74ad1c6730338b20aef77a… (mailing-list)
Frequently asked questions
- What is CVE-2021-26920?
- CVE-2021-26920 is a medium-severity vulnerability in Apache Druid, classified under Externally Controlled Reference to a Resource in Another Sphere. CVSS score: 6.5/10. Published 2021-07-02.
- How severe is CVE-2021-26920?
- Medium severity. CVSS v3 base score is 6.5 out of 10.
- Is CVE-2021-26920 known to be exploited?
- 10 public proof-of-concept repositories are indexed. Not currently listed in the CISA KEV catalog.