What is CVE-2021-44791?

CVE-2021-44791 is a medium-severity vulnerability in Apache Druid, classified under Cross-site Scripting. CVSS score: 6.1/10. Published 2022-07-07.

How severe is CVE-2021-44791?

Medium severity. CVSS v3 base score is 6.1 out of 10.

XSS in Apache Druid

CVE-2021-44791

In Apache Druid 0.22.1 and earlier, certain specially-crafted links result in unescaped URL parameters being sent back in HTML responses. This makes it possible to execute reflected XSS attacks.

Vulnerability class: XSS (Cross-Site Scripting)

Published 2022-07-07 · last modified 2026-06-17.

CVSS v3 metric

CVSS v3 base score 6.1 (Medium). Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N.

EPSS exploit prediction

EPSS: 0.022 (82.0th percentile), scored 2026-09-29.

Low probability of exploitation in the next 30 days, but still tracked. 82nd percentile — 82.0% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.

EPSS over last 30 days · oldest: 0.021 · newest: 0.022 · change: +0.001

Affected products

Apache Druid
Apache Software Foundation Druid — versions Apache Druid

Weakness classification (CWE)

CWE-79 — Cross-site Scripting

References

lists.apache.org/thread/lh2kcl4j45q7xj4w6rqf6kwf0mvyp2o6 (Mailing List, Vendor Advisory)

Frequently asked questions

What is CVE-2021-44791?: CVE-2021-44791 is a medium-severity vulnerability in Apache Druid, classified under Cross-site Scripting. CVSS score: 6.1/10. Published 2022-07-07.
How severe is CVE-2021-44791?: Medium severity. CVSS v3 base score is 6.1 out of 10.