GHSA-834c-x29c-f42c is a critical-severity (CVSS 9.6) CWE-87 vulnerability in org.xwiki.platform:xwiki-platform-flamingo-skin-resources. A fix is available for org.xwiki.platform:xwiki-platform-flamingo-skin-resources — see the affected versions and patch details below.
XWiki Platform vulnerable to reflected cross-site scripting via xredirect parameter in delete template
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 GHSA-834c-x29c-f42c.
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
GHSA-834c-x29c-f42c 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 376,715 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-skin-resources☕org.xwiki.platform:xwiki-platform-flamingo-skin-resourcesReal-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
Users are able to forge an URL with a payload allowing to inject Javascript in the page (XSS). It's possible to exploit the delete template to perform a XSS, e.g. by using URL such as:
xwiki/bin/get/FlamingoThemes/Cerulean?xpage=xpart&vm=delete.vm&xredirect=javascript:alert(document.domain)
This vulnerability exists since XWiki 6.0-rc-1.
Patches
The vulnerability has been patched in XWiki 14.10.6 and 15.1. Note that a partial patch has been provided in 14.10.5 but wasn't enough to entirely fix the vulnerability.
Workarounds
It's possible to workaround the vulnerability by editing the template delete.vm to perform checks on it, but note that the appropriate fix involves new APIs that have been recently introduced in XWiki. See the referenced jira tickets.
References
- Jira ticket about the original vulnerability: https://jira.xwiki.org/browse/XWIKI-20341
- Commit containing the first fix in the template: https://github.com/xwiki/xwiki-platform/commit/e80d22d193df364b07bab7925572720f91a8984a
- Jira ticket about the second part of the vulnerability found after 14.10.5: https://jira.xwiki.org/browse/XWIKI-20672
- Commits containing the second fix in the template:
- Introduction of the macro used for fixing all those vulnerabilities: https://jira.xwiki.org/browse/XWIKI-20583
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
Attribution
This vulnerability has been reported by René de Sain @renniepak.
Affected Packages
| Ecosystem | Package | Vulnerable range | Fix |
|---|---|---|---|
| ☕Maven | org.xwiki.platform:xwiki-platform-flamingo-skin-resources | ≥ 6.0-rc-1&&< 14.10.6 | 14.10.6org.xwiki.platform:xwiki-platform-flamingo-skin-resources:14.10.6 |
| ☕Maven | org.xwiki.platform:xwiki-platform-flamingo-skin-resources | ≥ 15.0-rc-0&&< 15.1 | 15.1org.xwiki.platform:xwiki-platform-flamingo-skin-resources:15.1 |
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-skin-resources, including transitive dependencies — a direct dependency you never call can still pull in a vulnerable version.
Fix
Update org.xwiki.platform:xwiki-platform-flamingo-skin-resources to 14.10.6 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms GHSA-834c-x29c-f42c 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 GHSA-834c-x29c-f42c can be triaged on real exposure rather than presence alone.
Tailored to GHSA-834c-x29c-f42c. Runtime protection reduces exposure until a permanent patch is applied and verified — it complements patching, it doesn't replace it.
How to detect GHSA-834c-x29c-f42c
A community-maintained Nuclei template exists for this CVE. You can scan for it directly:
nuclei -id ghsa-834c-x29c-f42c -u https://target- Template
- XWiki >= 6.0-rc-1 - Cross-Site Scripting
- Severity
- medium
- Impact
- Successful exploitation could lead to cross-site scripting.
- Remediation
- This vulnerability has been patched in XWiki 14.10.6,15.1.
Template by ProjectDiscovery nuclei-templates (ritikchaddha), MIT licensed. View the full template. Scan only systems you are authorised to test.
Frequently Asked Questions
Is GHSA-834c-x29c-f42c in your dependencies?
O3 Security finds GHSA-834c-x29c-f42c across Maven dependencies, including transitive ones, and its impact-aware SCA ranks findings by whether your code actually calls the vulnerable path.