How severe is CVE-2023-30537?

CVE-2023-30537 has a CVSS score of 9.9/10, rated CRITICAL. Immediate patching is strongly recommended.

Which packages are affected by CVE-2023-30537?

CVE-2023-30537 affects the following packages: org.xwiki.platform:xwiki-platform-flamingo-theme-ui (Maven), org.xwiki.platform:xwiki-platform-flamingo-theme-ui (Maven), org.xwiki.platform:xwiki-platform-flamingo-theme-ui (Maven). Ecosystems affected: Maven.

How do I fix CVE-2023-30537?

Update org.xwiki.platform:xwiki-platform-flamingo-theme-ui to 13.10.11 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms CVE-2023-30537 is resolved across your whole dependency graph.

How do I detect CVE-2023-30537 in my Maven dependencies?

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

How do I mitigate CVE-2023-30537 if there is no patch (or I can't update yet)?

Stop passing untrusted input into the interpreter or shell: call the affected binary with an argument array rather than a composed command string, reject anything outside a strict allowlist of expected values, and run the component under an account that cannot reach beyond the work it legitimately does.

Is CVE-2023-30537 actively exploited in the wild?

Yes. There are 2 known exploit references for CVE-2023-30537, including 2 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-2023-30537?

CVE-2023-30537 has an EPSS (Exploit Prediction Scoring System) score of 1.0%, placing it in the 64th 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-2023-30537?

CVE-2023-30537 is classified as CWE-95 (CWE-95), Code Injection (CWE-94). These weakness types 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-2023-30537 published, and has it been updated?

CVE-2023-30537 was published on April 16, 2023 and was last updated on October 28, 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

CRITICAL severity

CVE-2023-30537 — xwiki-platform-flamingo-t…

CRITICALFix: xwiki/xwiki-platform@df596f1

CVE-2023-30537 is a critical-severity (CVSS 9.9) CWE-95 vulnerability in org.xwiki.platform:xwiki-platform-flamingo-theme-ui. 2 public exploit or proof-of-concept references are indexed, so weaponization risk is real. A fix is available for org.xwiki.platform:xwiki-platform-flamingo-theme-ui — see the affected versions and patch details below.

org.xwiki.platform:xwiki-platform-flamingo-theme-ui vulnerable to privilege escalation

Also known asGHSA-vrr8-fp7c-7qgp

Published

Apr 16, 2023

Updated

Oct 28, 2026

Affected

3 pkgs

Patched

3 / 3

Exploits

2 known

Exploitation data as of Oct 29, 2026 · OSV.dev, NVD, FIRST.org (EPSS)

Exploitation Status

Proof-of-concept exploit code exists

CISA’s SSVC triage found public proof-of-concept exploit code for this CVE, though no confirmed active exploitation.
A successful exploit gives an attacker total control of the affected component, not partial access.

Exploitation and automatability from CISA’s SSVC triage for CVE-2023-30537.

EPSS Exploitation Probability

via FIRST.org ↗

1.0%probability of exploitation in next 30 days

Lower Risk0.00%

Lower risk than most CVEs64th percentile — riskier than 64% 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

3 pkgs affected

☕org.xwiki.platform:xwiki-platform-flamingo-theme-ui☕org.xwiki.platform:xwiki-platform-flamingo-theme-ui☕org.xwiki.platform:xwiki-platform-flamingo-theme-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

Impact

Any user with the right to add an object on a page can execute arbitrary Groovy, Python or Velocity code in XWiki leading to full access to the XWiki installation. The root cause is improper escaping of the styles properties FlamingoThemesCode.WebHome. This page is installed by default.

Reproduction Steps

Steps to reproduce:

As a user without script or programming rights, edit your user profile with the object editor (enable advanced mode if necessary to get access) and add an object of type "Theme Class" of "FlamingoThemesCode". In the field "body-bg" (all other fields should work, too) add the following text:

{{/html}} {{async async="true" cached="false" context="doc.reference"}}{{groovy}}println("Hello " + "from groovy!"){{/groovy}}{{/async}}

Click "Save & View"
Open <xwiki-host>/xwiki/bin/view/FlamingoThemesCode/WebHomeSheet where <xwiki-host> is the URL of your XWiki installation

Expected result:

The list of color themes either doesn't include the user's profile or displays a regular preview.

Actual result:

The user's profile is listed as color theme but instead of the little preview the message

Failed to execute the [html] macro. Cause: [When using HTML content inline, you can only use inline HTML content. Block HTML content (such as tables) cannot be displayed. Try leaving an empty line before and after the macro.]. Click on this message for details.
Hello from groovy!">

is displayed. This shows that a Groovy macro with content created by the user has been executed and thus demonstrates a privilege escalation from simple user account to programming rights.

Patches

The vulnerability has been patched in XWiki 13.10.11, 14.4.7 and 14.10.

Workarounds

The issue can be fixed by applying this patch on FlamingoThemesCode.WebHomeSheet.

References

For more information

If you have any questions or comments about this advisory:

Open an issue in Jira XWiki.org
Email us at Security Mailing List

Affected Packages

3 total 3 fixed

Ecosystem	Package	Vulnerable range	Fix
☕Maven	`org.xwiki.platform:xwiki-platform-flamingo-theme-ui`	≥ 12.6.6&&< 13.10.11	13.10.11`org.xwiki.platform:xwiki-platform-flamingo-theme-ui:13.10.11`
☕Maven	`org.xwiki.platform:xwiki-platform-flamingo-theme-ui`	≥ 14.0-rc-1&&< 14.4.7	14.4.7`org.xwiki.platform:xwiki-platform-flamingo-theme-ui:14.4.7`
☕Maven	`org.xwiki.platform:xwiki-platform-flamingo-theme-ui`	≥ 14.5&&< 14.10	14.10`org.xwiki.platform:xwiki-platform-flamingo-theme-ui:14.10`

Affected Products

1 product · 3 configurations

Application

xwikixwiki

≥ 14.5 && < 14.10

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.

XWiki Platform is a generic wiki platform offering runtime services for …

jira.xwiki.orgNVDApr 2023

Report on github.com

github.comNVDApr 2023

Detection & mitigation playbook

Open-source dependency

Detect
Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for org.xwiki.platform:xwiki-platform-flamingo-theme-ui, including transitive dependencies — a direct dependency you never call can still pull in a vulnerable version.
Fix
Update org.xwiki.platform:xwiki-platform-flamingo-theme-ui to 13.10.11 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms CVE-2023-30537 is resolved across your whole dependency graph.
Workarounds
Stop passing untrusted input into the interpreter or shell: call the affected binary with an argument array rather than a composed command string, reject anything outside a strict allowlist of expected values, and run the component under an account that cannot reach beyond the work it legitimately does.

Frequently Asked Questions

### Impact Any user with the right to add an object on a page can execute arbitrary Groovy, Python or Velocity code in XWiki leading to full access to the XWiki installation. The root cause is improper escaping of the styles properties `FlamingoThemesCode.WebHome`. This page is installed by default. #### Reproduction Steps **Steps to reproduce**: - As a user without script or programming rights, edit your user profile with the object editor (enable advanced mode if necessary to get access) and add an object of type "Theme Class" of "FlamingoThemesCode". In the field "body-bg" (all other fi