Vulnerability report

Exploited in the wild High confidence Not in CISA KEV

CVE-2021-25646

Apache Druid

Apache Software Foundation / Apache Druid · 0.20.0 and earlier to <= 0.20.0

Severity
CVSS 8.8 · High
Confidence
High
Exploit status
Exploited in the wild
EPSS
99.2%
First observed
Last observed

Decision summary

What security teams need to know first

Direct answers before the deeper technical record.

What it is

CVE-2021-25646 is a vulnerability affecting Apache Software Foundation Apache Druid. Apache Druid includes the ability to execute user-provided JavaScript code embedded in various types of requests. This functionality...

Is it exploited?

Yes. KEV Intelligence tracks this CVE as a known exploited vulnerability. Confidence is high.

Who is affected?

Apache Software Foundation / Apache Druid 0.20.0 and earlier to <= 0.20.0.

What should we do?

Prioritize remediation. Validate affected assets and apply vendor fixes on an accelerated timeline.

Overview

Apache Druid includes the ability to execute user-provided JavaScript code embedded in various types of requests

Apache Druid includes the ability to execute user-provided JavaScript code embedded in various types of requests. This functionality is intended for use in high-trust environments, and is disabled by default.

However, in Druid 0.20.0 and earlier, it is possible for an authenticated user to send a specially-crafted request that forces Druid to run user-provided JavaScript code for that request, regardless of server configuration. This can be leveraged to execute code on the target machine with the privileges of the Druid server process.

Vendor Product Affected Status
Apache Software Foundation Apache Druid Through 0.20.0 Affected
Published
29 Jan 2021
Exploitation Reported
27 Apr 2025
Attack vector
Remote
Complexity
Low
Privileges
Low
User interaction
None

Tags

metasploit nuclei_scanner java apache

CVE References

Exploitation evidence

Why KEV Intelligence marks this CVE as exploited

Third-party attestation and first-party sensor observation are shown separately so teams can judge the evidence chain.

Exploited in the wild

The Shadowserver

Recorded 27 Apr 2025

Independent exploitation attestation added to the KEV Intelligence record.

Proof of concept available

GitHub

Recorded 12 Dec 2021

Public scanner or PoC coverage increases practical exploitability.

Known exploited vulnerability sources

Per-source evidence links for KEV attestations are available through the KEV Intelligence Pro API.

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Source Added
The Shadowserver First 2025-04-28 00:00 UTC

Detection

Operational artifacts and observed signals

Make the evidence actionable in scanner, SOC, and edge-control workflows.

Observed signals

Request targets
0
User-Agents
0

Raw values available in Pro and Enterprise.

Virtual patch status

No KEV Intelligence virtual patch is currently available. Future rules ship for ModSecurity, Cloudflare, and AWS WAF.

Learn about virtual patches →

Scanner Artifacts

Scanner and exploit-framework references linked to this CVE.

Risk and context

Severity, weaknesses, and research context

CVSS v3.1

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

EPSS

99.2%

All CVSS Scores

CVSS v3.1 8.8 High

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

CVSS v2.0 9.0 High

AV:N/AC:L/Au:S/C:C/I:C/A:C

Potential Proof of Concepts

These PoCs are unverified and could contain malware. Use at your own risk.

Apache Druid - Remote Code Execution

nuclei · Created Unknown

apache_druid_js_rce

metasploit · Created Unknown

Metasploit module for CVE-2021-25646

Timeline

From disclosure to observed exploitation

  1. Metasploit module available

    Exploit module available

  2. Public PoC available

    Public proof-of-concept code published

  3. Added to KEV Intelligence KEV Feed

    High-confidence, third-party attested exploitation

  4. Nuclei template available

    Scanner coverage available

  5. CVE published

    Vulnerability disclosed publicly

  6. CVE ID reserved

    Identifier reserved by the CNA

Pro API

Automate this intelligence

Confidence, exploit status, sensor telemetry, PoCs, scanner integrations, mentions, and tags are available programmatically for VM, SOC, and CTI workflows.

  • Evidence confidence and provenance
  • First-party sensor telemetry
  • PoC and scanner references
  • Affected versions and enrichment
  • Automation-ready JSON delivery

GET /api/v2/pro/kevs/CVE-2021-25646

Free JSON includes basic KEV fields
{
  "cve_id": "CVE-2021-25646",
  "confidence": "High",
  "cvss_score": 8.8,
  "cvss_estimated": false,
  "epss_score": 0.99193,
  "exploit_status": {
    "exploited_in_the_wild": true,
    "active_exploitation_observed": false
  },
  "sensor_telemetry": { "attempts": 0, "sensors": 0 }
}

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