How severe is CVE-2021-29039?

CVE-2021-29039 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-2021-29039?

CVE-2021-29039 affects the following packages: com.liferay.portal:release.portal.bom (Maven). Ecosystems affected: Maven.

How do I fix CVE-2021-29039?

Update com.liferay.portal:release.portal.bom to 7.3.5 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms CVE-2021-29039 is resolved across your whole dependency graph.

How do I detect CVE-2021-29039 in my Maven dependencies?

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

How do I mitigate CVE-2021-29039 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-2021-29039 actively exploited in the wild?

No public exploit code has been indexed for CVE-2021-29039 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-2021-29039?

CVE-2021-29039 has an EPSS (Exploit Prediction Scoring System) score of 0.8%, placing it in the 55th 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-2021-29039?

CVE-2021-29039 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-2021-29039 published, and has it been updated?

CVE-2021-29039 was published on May 16, 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

MEDIUM severity

CVE-2021-29039 — release.portal.bom

MEDIUM

CVE-2021-29039 is a medium-severity (CVSS 6.1) Cross-site Scripting (XSS) vulnerability in com.liferay.portal:release.portal.bom. A fix is available for com.liferay.portal:release.portal.bom — see the affected versions and patch details below.

Liferay Portal Vulnerable to Cross-Site Scripting (XSS) via Categories Admin Page

Also known asGHSA-239w-4f3w-cfcv

Published

May 16, 2021

Updated

Oct 24, 2026

Affected

1 pkg

Patched

1 / 1

Exploits

None indexed

Exploitation data as of Nov 4, 2026 · OSV.dev, NVD, FIRST.org (EPSS)

EPSS Exploitation Probability

via FIRST.org ↗

0.8%probability of exploitation in next 30 days

Lower Risk0.00%

Lower risk than most CVEs55th percentile — riskier than 55% 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

☕com.liferay.portal:release.portal.bom

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

Cross-site scripting (XSS) vulnerability in the Asset module's categories administration page in Liferay Portal 7.3.4 allows remote attackers to inject arbitrary web script or HTML via the site name.

Affected Packages

1 total 1 fixed

Ecosystem	Package	Vulnerable range	Fix
☕Maven	`com.liferay.portal:release.portal.bom`	≥ 7.3.4&&< 7.3.5	7.3.5`com.liferay.portal:release.portal.bom:7.3.5`

Affected Products

1 product · 1 configurations

Application

liferay portalliferay

1 version

7.3.4

Detection & mitigation playbook

Open-source dependency

Detect
Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for com.liferay.portal:release.portal.bom, including transitive dependencies — a direct dependency you never call can still pull in a vulnerable version.
Fix
Update com.liferay.portal:release.portal.bom to 7.3.5 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms CVE-2021-29039 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

Cross-site scripting (XSS) vulnerability in the Asset module's categories administration page in Liferay Portal 7.3.4 allows remote attackers to inject arbitrary web script or HTML via the site name.

O3 Security · Impact-Aware SCA

Is CVE-2021-29039 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

liferay-portal

2.5/10

Code-Review0/10

Maintained10/10

Branch-Protection0/10

Assessed Nov 2, 2026

Timeline

Disclosed

May 16, 2021

Last updated

Oct 24, 2026

Identifiers

CVE-2021-29039

GHSA-239w-4f3w-cfcv

References

Advisoryportal.liferay.dev Advisorynvd.nist.gov · CVE 2021 29039 Webweb.archive.org Webliferay.com Packagegithub.com · liferay portal

Related vulnerabilities

This CVE is medium severity; 8 of 8 other CVEs affecting release.portal.bom are rated as high or higher (top: high).

CVE-2025-62264CVE-2025-62265CVE-2025-62257CVE-2025-62266CVE-2025-62258CVE-2025-62259CVE-2025-62260CVE-2025-62261

Provenance

Sources

OSV.devNVDFIRST.org (EPSS)

Last verifiedOct 24, 2026