How severe is CVE-2021-3914?

CVE-2021-3914 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-2021-3914?

CVE-2021-3914 affects the following packages: io.smallrye:smallrye-health-ui (Maven). Ecosystems affected: Maven.

How do I fix CVE-2021-3914?

Update io.smallrye:smallrye-health-ui to 3.1.2 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms CVE-2021-3914 is resolved across your whole dependency graph.

How do I detect CVE-2021-3914 in my Maven dependencies?

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

How do I mitigate CVE-2021-3914 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-2021-3914 actively exploited in the wild?

No public exploit code has been indexed for CVE-2021-3914 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-2021-3914?

CVE-2021-3914 has an EPSS (Exploit Prediction Scoring System) score of 0.5%, placing it in the 44th 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-2021-3914?

CVE-2021-3914 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.

Is there exploit tooling available for CVE-2021-3914?

2 Metasploit modules reference CVE-2021-3914, 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-2021-3914 published, and has it been updated?

CVE-2021-3914 was published on August 26, 2022 and was last updated on February 16, 2024. 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-2021-3914 — smallrye-health-ui

MEDIUMFix: smallrye/smallrye-health#333

CVE-2021-3914 is a medium-severity (CVSS 6.1) Cross-site Scripting (XSS) vulnerability in io.smallrye:smallrye-health-ui. A fix is available for io.smallrye:smallrye-health-ui — see the affected versions and patch details below.

SmallRye Health UI Cross-site Scripting vulnerability

Published

Aug 26, 2022

Updated

Feb 16, 2024

Affected

1 pkg

Patched

1 / 1

Exploits

None indexed

Exploitation data as of Oct 31, 2026 · OSV.dev, NVD, FIRST.org (EPSS)

EPSS Exploitation Probability

via FIRST.org ↗

0.5%probability of exploitation in next 30 days

Lower Risk+0.01%

Lower risk than most CVEs44th percentile — riskier than 44% 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

☕io.smallrye:smallrye-health-ui

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

It was found that the smallrye health metrics UI component did not properly sanitize some user inputs. An attacker could use this flaw to conduct cross-site scripting attacks.

Affected Packages

1 total 1 fixed

Ecosystem	Package	Vulnerable range	Fix
☕Maven	`io.smallrye:smallrye-health-ui`	all versions	3.1.2`io.smallrye:smallrye-health-ui:3.1.2`

Affected Products

3 products · 4 configurations

Application

build of quarkusredhat

< 2.7.5

range

Application

openshift application runtimesredhat

1 version

1.0

Application

smallrye healthredhat

all

Detection & mitigation playbook

Open-source dependency

Detect
Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for io.smallrye:smallrye-health-ui, including transitive dependencies — a direct dependency you never call can still pull in a vulnerable version.
Fix
Update io.smallrye:smallrye-health-ui to 3.1.2 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms CVE-2021-3914 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.

Fixing This On Your OS

If you run this on a Linux distribution, patch through your package manager against the distro's own security advisory below — it tracks the exact backported fix for your release, which can ship on a different timeline (and sometimes a different severity) than the upstream project.

Red HatModerate

Product	Fixed in	Advisory
Red Hat build of Quarkus 2.7.5	`smallrye-health-ui`	RHSA-2022:4623

Frequently Asked Questions

It was found that the smallrye health metrics UI component did not properly sanitize some user inputs. An attacker could use this flaw to conduct cross-site scripting attacks.

O3 Security · Impact-Aware SCA

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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

OpenSSF Scorecard

Package health score

smallrye-health

3.2/10

Maintained0/10

Code-Review0/10

Branch-Protection8/10

Assessed Oct 26, 2026

Timeline

Disclosed

Aug 26, 2022

Last updated

Feb 16, 2024

Identifiers

CVE-2021-3914

References

Advisorynvd.nist.gov · CVE 2021 3914 Webgithub.com Webgithub.com · 01b25a038824887363cd413d8cd14052f5fc3541 Webgithub.com · 47a33f19f5bb1e4216a15f3aee6ca3b1e2ccba59 Webaccess.redhat.com · CVE 2021 3914 Webbugzilla.redhat.com · show bug.cgi Packagegithub.com · smallrye health

Related vulnerabilities

This CVE is medium severity; 8 of 8 other CVEs with CWE-79 are rated as high or higher (top: critical).

CVE-2026-44267CVE-2026-96632CVE-2026-9086CVE-2026-118246CVE-2026-118251CVE-2026-118253CVE-2026-116797CVE-2026-118244Browse all CWE-79

Provenance

Sources

OSV.devNVDFIRST.org (EPSS)

Last verifiedFeb 16, 2024

CVE-2021-3914 — smallrye-health-ui

EPSS Exploitation Probability

How urgent is this, really

Where this sits among everything scored

Real-World Exposure

Description

Affected Packages

Affected Products

Detection & mitigation playbook

Detect

Fix

Workarounds

Fixing This On Your OS

Frequently Asked Questions

Is CVE-2021-3914 in your dependencies?