How severe is CVE-2021-44791?

CVE-2021-44791 has a CVSS score of 6.1/10, rated MEDIUM. Review your exposure and patch according to your risk tolerance.

Which packages are affected by CVE-2021-44791?

CVE-2021-44791 affects the following packages: org.apache.druid:druid (Maven). Ecosystems affected: Maven.

How do I fix CVE-2021-44791?

Update org.apache.druid:druid to 0.23.0 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms CVE-2021-44791 is resolved across your whole dependency graph.

How do I detect CVE-2021-44791 in my Maven dependencies?

Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for org.apache.druid:druid, including transitive dependencies — a direct dependency you never call can still pull in a vulnerable version.

How do I mitigate CVE-2021-44791 if there is no patch (or I can't update yet)?

Escape or sanitise the affected output on the server side rather than relying on client-side filtering, and add a Content-Security-Policy that blocks inline script execution so injected markup cannot run even if it reaches the page.

Is CVE-2021-44791 actively exploited in the wild?

No public exploit code has been indexed for CVE-2021-44791 yet. This does not mean the vulnerability cannot be exploited — absence of public exploits does not imply safety. Apply the recommended fix and use O3 Security to monitor your exposure.

What is the EPSS score for CVE-2021-44791?

CVE-2021-44791 has an EPSS (Exploit Prediction Scoring System) score of 2.2%, placing it in the 83th percentile of all CVEs. EPSS is maintained by FIRST.org and estimates the probability that a vulnerability will be exploited in the wild within the next 30 days. This score indicates relatively lower exploitation probability, though the CVSS severity should still guide your patching priority.

What type of vulnerability is CVE-2021-44791?

CVE-2021-44791 is classified as Cross-site Scripting (XSS) (CWE-79). This weakness type describe the underlying flaw category, which helps determine the potential impact and the right class of mitigation. This is a high-impact weakness class that often enables remote code execution or data exposure.

When was CVE-2021-44791 published, and has it been updated?

CVE-2021-44791 was published on July 7, 2022 and was last updated on October 24, 2026. Advisory data evolves as severity scores, affected ranges, and exploit intelligence are revised — always check the latest version of the advisory before acting.

☕

☕ Maven

Not in CISA KEV

MEDIUM severity

CVE-2021-44791 — druid

MEDIUM

CVE-2021-44791 is a medium-severity (CVSS 6.1) Cross-site Scripting (XSS) vulnerability in org.apache.druid:druid. A fix is available for org.apache.druid:druid — see the affected versions and patch details below.

Apache Druid before 0.23.0 vulnerable to reflected XSS via unescaped URL parameters

Also known asGHSA-8rmv-98m4-g5c6

Published

Jul 7, 2022

Updated

Oct 24, 2026

Affected

1 pkg

Patched

1 / 1

Exploits

None indexed

Exploitation data as of Nov 2, 2026 · OSV.dev, NVD, FIRST.org (EPSS)

EPSS Exploitation Probability

via FIRST.org ↗

2.2%probability of exploitation in next 30 days

Lower Risk0.00%

Lower risk than most CVEs83th percentile — riskier than 83% of all scored CVEsHighest risk

Probability of exploitation in the next 30 days, from FIRST.org EPSS.

How urgent is this, really

Where this sits among everything scored

Real-World Exposure

1 pkg affected

☕org.apache.druid:druid

Real-time download stats are indexed for npm and PyPI packages. This vulnerability affects Maven packages — download data is not available via public APIs for these ecosystems.

Description

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. This issue is patched in version 0.23.0.

Affected Packages

1 total 1 fixed

Ecosystem	Package	Vulnerable range	Fix
☕Maven	`org.apache.druid:druid`	all versions	0.23.0`org.apache.druid:druid:0.23.0`

Affected Products

1 product · 1 configurations

Application

druidapache

≤ 0.22.1

range

Detection & mitigation playbook

Open-source dependency

Detect
Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for org.apache.druid:druid, including transitive dependencies — a direct dependency you never call can still pull in a vulnerable version.
Fix
Update org.apache.druid:druid to 0.23.0 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms CVE-2021-44791 is resolved across your whole dependency graph.
Workarounds
Escape or sanitise the affected output on the server side rather than relying on client-side filtering, and add a Content-Security-Policy that blocks inline script execution so injected markup cannot run even if it reaches the page.

Frequently Asked Questions

O3 Security · Impact-Aware SCA

Is CVE-2021-44791 in your dependencies?

Find it across Maven, including transitive dependencies.

Scan my dependencies How O3 SCA works

CVSS Score

6.1/10CVSS v3 base

Vector breakdown

Attack Vector

Network

Attack Complexity

Low

Privileges Required

None

User Interaction

Required

Scope

Changed

Confidentiality

Low

Integrity

Low

Availability

None

Raw vector

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

CWE Classification

CWE-79Cross-site Scripting (XSS)

Weaponization

No Nuclei template, Metasploit module or public proof-of-concept found.

OpenSSF Scorecard

Package health score

druid

7.5/10

Maintained10/10

Code-Review10/10

Branch-ProtectionN/A

Assessed Oct 26, 2026

Timeline

Disclosed

Jul 7, 2022

Last updated

Oct 24, 2026

Identifiers

CVE-2021-44791

GHSA-8rmv-98m4-g5c6

References

Advisorylists.apache.org · lh2kcl4j45q7xj4w6rqf6kwf0mvyp2o6 Advisorynvd.nist.gov · CVE 2021 44791 Packagegithub.com · druid

Related vulnerabilities

Also affects druid

This CVE is medium severity; 6 of 7 other CVEs affecting druid are rated as high or higher (top: critical).

CVE-2025-59390CVE-2025-27888CVE-2024-45537CVE-2022-28889CVE-2020-1958CVE-2021-26919CVE-2021-25646

Same weakness: CWE-79

This CVE is medium severity, in line with the other 1 CVE with CWE-79.

CVE-2026-55649Browse all CWE-79

Provenance

Sources

OSV.devNVDFIRST.org (EPSS)

Last verifiedOct 24, 2026