How severe is CVE-2021-25646?

CVE-2021-25646 has a CVSS score of 8.8/10, rated HIGH. Immediate patching is strongly recommended.

Which packages are affected by CVE-2021-25646?

CVE-2021-25646 affects the following packages: org.apache.druid:druid (Maven). Ecosystems affected: Maven.

How do I fix CVE-2021-25646?

Update org.apache.druid:druid to 0.20.1 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms CVE-2021-25646 is resolved across your whole dependency graph.

How do I detect CVE-2021-25646 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-2021-25646 if there is no patch (or I can't update yet)?

If you can't upgrade right away: gate or disable the affected feature, validate untrusted input at the boundary, and avoid passing attacker-controlled data into the vulnerable path. O3's runtime protection blocks exploitation in production as an interim safeguard until the upgrade lands.

Is CVE-2021-25646 actively exploited in the wild?

Yes. There are 14 known exploit references for CVE-2021-25646, including 8 in-the-wild exploitations observed on GitHub and other sources. Treat this as actively exploitable and prioritize patching immediately. All exploit code should only be run in an isolated sandbox environment for research or authorized testing — never against production systems without explicit written authorization.

What is the EPSS score for CVE-2021-25646?

CVE-2021-25646 has an EPSS (Exploit Prediction Scoring System) score of 99.0%, placing it in the 100th 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. A score above 50% indicates significantly elevated exploitation risk — immediate patching is strongly recommended.

Is there exploit tooling available for CVE-2021-25646?

A Nuclei detection template exists for CVE-2021-25646, meaning automated scanners can fingerprint it. A Metasploit module references CVE-2021-25646, which lowers the barrier to weaponization. Public exploit tooling significantly increases real-world risk — prioritize patching and ensure detection coverage. Exploit tooling should only ever be used in isolated, authorized testing environments.

When was CVE-2021-25646 published, and has it been updated?

CVE-2021-25646 was published on January 29, 2021 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

HIGH severity

CVE-2021-25646 — druid

HIGH

CVE-2021-25646 is a high-severity (CVSS 8.8) vulnerability in org.apache.druid:druid. 14 public exploit references exist, so weaponization risk is real. A fix is available for org.apache.druid:druid — see the affected versions and patch details below.

Code injection in Apache Druid

Also known asGHSA-wrqf-rrrw-w3mg

Published

Jan 29, 2021

Updated

Oct 24, 2026

Affected

1 pkg

Patched

1 / 1

Exploits

14 known

Exploitation data as of Oct 23, 2026 · OSV.dev, NVD, FIRST.org (EPSS)

EPSS Exploitation Probability

via FIRST.org ↗

99.0%probability of exploitation in next 30 days

Very High Risk0.00%

Lower risk than most CVEs100th percentile — riskier than 100% of all scored CVEsHighest risk

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

How urgent is this, really

CVE-2021-25646 by exploitation likelihood (EPSS) against impact (CVSS). In the shaded patch-first corner (EPSS 50%+, CVSS 7.0+).

Where this sits among everything scored

Of 395,249 CVEs with a current EPSS score, this one falls in the ≥ 90% band (highlighted). Counts from FIRST.org, log-scaled.

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

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.

Affected Packages

1 total 1 fixed

Ecosystem	Package	Vulnerable range	Fix
☕Maven	`org.apache.druid:druid`	all versions	0.20.1`org.apache.druid:druid:0.20.1`

Affected Products

1 product · 1 configurations

Application

druidapache

≤ 0.20.0

range

Exploits & PoCs

Research use only. For defensive security, authorized penetration testing, and academic research only. Never execute exploit code against systems without explicit written authorization.