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 references exist, 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
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
EPSS (Exploit Prediction Scoring System) is a daily probability model maintained by FIRST.org. It estimates the likelihood a CVE will be exploited in production environments within the next 30 days, derived from real-world threat intelligence signals.
How urgent is this, really
CVE-2023-30537 plotted by exploitation likelihood (EPSS) against impact (CVSS). The shaded corner — EPSS 50%+ and CVSS 7.0+ — is where this CVE doesn't sit, though severity or exploitability alone can still warrant action.
Where this sits among everything scored
Of 377,636 CVEs with a current EPSS score, this one falls in the < 10% band (highlighted). Real counts from FIRST.org, not a sample — log-scaled since the landscape is heavily right-skewed.
Real-World Exposure
org.xwiki.platform:xwiki-platform-flamingo-theme-ui☕org.xwiki.platform:xwiki-platform-flamingo-theme-ui☕org.xwiki.platform:xwiki-platform-flamingo-theme-uiReal-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
- patch: https://github.com/xwiki/xwiki-platform/commit/df596f15368342236f8899ca122af8f3df0fe2e8
- Jira: https://jira.xwiki.org/browse/XWIKI-20280
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
| Ecosystem | Package | Vulnerable range | Fix |
|---|---|---|---|
| ☕Maven | org.xwiki.platform:xwiki-platform-flamingo-theme-ui | ≥ 12.6.6&&< 13.10.11 | 13.10.11org.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 | 14.4.7org.xwiki.platform:xwiki-platform-flamingo-theme-ui:14.4.7 |
| ☕Maven | org.xwiki.platform:xwiki-platform-flamingo-theme-ui | ≥ 14.5&&< 14.10 | 14.10org.xwiki.platform:xwiki-platform-flamingo-theme-ui:14.10 |
Research use only. For defensive security, authorized penetration testing, and academic research only. Never execute exploit code against systems without explicit written authorization.
Detection & mitigation playbook
Open-source dependencyDetect
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
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.
How O3 protects you
O3 Security's impact-aware SCA analyses which vulnerable code paths your application actually calls, so a match like CVE-2023-30537 can be triaged on real exposure rather than presence alone.
Tailored to CVE-2023-30537. Runtime protection reduces exposure until a permanent patch is applied and verified — it complements patching, it doesn't replace it.
Frequently Asked Questions
Is CVE-2023-30537 in your dependencies?
O3 Security finds CVE-2023-30537 across Maven dependencies, including transitive ones, and its impact-aware SCA ranks findings by whether your code actually calls the vulnerable path.