CVE-2021-44791Network attack vector

Reflected XSS via HTML error responses

Published Jul 7, 2022 · Updated Aug 4, 2024

Reflected XSS in Apache Druid 0.22.1 and earlier allows remote attackers to execute script in a victim's browser via crafted links. Affected HTTP error handlers place invalid URL parameters into text/html response bodies without output encoding or a non-HTML media type. A victim must follow an attacker-crafted link; the resulting script runs in the browser's Druid origin and can read or alter data accessible to that session.

CVSS severity6.1
Medium
EPSS probability2.15%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Reflected XSS in Apache Druid 0.22.1 and earlier allows remote attackers to execute script in a victim's browser via crafted links. Affected HTTP error handlers place invalid URL parameters into text/html response bodies without output encoding or a non-HTML media type. A victim must follow an attacker-crafted link; the resulting script runs in the browser's Druid origin and can read or alter data accessible to that session.

The record

CVE
CVE-2021-44791
Published
Jul 7, 2022
Updated
Aug 4, 2024
Vendor
The Apache Software Foundation
Product
Apache Druid
Classifications
CWE-79, T1203
Attack vector
network
Privileges
unauthenticated

Timeline

How it unfolded

  1. Jul 7, 2022CVE publishedPublication date reported by the CVE source.
  2. Aug 4, 2024Record updatedLatest update available in the CVE record.

Exploitability

Present is not the same as exploitable

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Is a vulnerable build present?

Compare these published version ranges with your installed build and any vendor patches.

  1. Affected versionversion=Apache Druid <=0.22.1

What conditions does exploitation require?

Attack vectornetwork
Required privilegesunauthenticated

What is affected?

The Apache Software Foundation · Apache Druidversion=Apache Druid <=0.22.1

Published CVSS scores

6.1GitLab Advisory DatabaseCVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N

CVSS describes severity. EPSS estimates exploitation probability.

Attacks

What attackers are doing with it

Daily unique IPs observed by Shadowserver honeypots for known exploited vulnerabilities (KEVs). Missing observations do not establish an absence of attacks.

Daily unique IPsNo honeypot observations are available for this CVE in the selected window.

No observations available

Sep 10, 2026Sep 16, 2026
Latest reporting daySep 16, 2026
Latest daily unique IPsUnavailable
Prior 30-day averageUnavailable
SourceShadowserver honeypots (KEV)
Vectornetwork
Privilegesunauthenticated
Known exploitationUnconfirmed
Public exploitUnconfirmed

Weakness, pattern, technique

CWE-79Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting')
T1203Exploitation for Client Execution

Public exploit references

No public exploit references are available in this record.

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Technologies

Your stack

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Your stack

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