Cross-site Scripting by SVG upload in xwiki-platform

Exploitation

No confirmed exploitation recorded. Patch Next marks exploitation only from CISA KEV.

CVSS

4.1 · CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:C/C:L/I:N/A:N

EPSS

• CVE-2021-43841: 0.87% estimated exploitation activity in the next 30 days; percentile 58.85 (FIRST EPSS, 2026-11-03). This is a model estimate, not proof of exploitation or customer exposure.

As published by the source; long descriptions are shortened.

Impact When using default XWiki configuration, it's possible for an attacker to upload an SVG containing a script executed when executing the download action on the file. Patches This problem has been patched so that the default configuration doesn't allow to display the SVG files in the browser. Workarounds This issue can be fixed without the patch by setting properly the configuration to download or display files, see: https://www.xwiki.org/xwiki/bin/view/Documentation/AdminGuide/Attachments#HAttachmentdisplayordownload References https://jira.xwiki.org/browse/XWIKI-18368 For more information If you have any questions or comments about this advisory: Open an issue in Jira Email us at security ML

Published by the source

10 Feb 2022, 22:42 UTC

Last modified by the source

26 Sep 2023, 12:00 UTC

Source last checked

26 Oct 2026, 16:12 UTC

1. Revision 1 · created · 26 Oct 2026

   Published from ghsa record GHSA-9jq9-c2cv-pcrj

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# Patch Next advisory brief: CVE-2021-43841

Advisory: Cross-site Scripting by SVG upload in xwiki-platform
IDs: CVE-2021-43841, GHSA-9jq9-c2cv-pcrj
Record: https://patchnext.com/advisories/cve-2021-43841 (revision 1, source checked 26 Oct 2026, 16:12 UTC)
Inventory: none attached. This brief comes from a public page and does not say whether any deployment is affected.
Severity: Medium (CVSS 4.1)
Exploitation: no confirmed exploitation recorded. Patch Next confirms exploitation only from CISA KEV.
Vendor response: Vendor fix available; fixed versions by package: org.xwiki.platform:xwiki-platform-tool-configuration-resources 13.3RC1, 12.10.6; org.xwiki.platform:xwiki-platform-oldcore 13.3RC1, 12.10.6. A vendor fix does not mean a deployment is fixed.

## Affected components
- Maven org.xwiki.platform:xwiki-platform-tool-configuration-resources: affected >= 13.0, <= 13.2; < 12.10.6; fixed in 13.3RC1, 12.10.6
- Maven org.xwiki.platform:xwiki-platform-oldcore: affected < 12.10.6; >= 13.0, <= 13.2; fixed in 13.3RC1, 12.10.6

## Suggested inspection (read-only)
- Maven org.xwiki.platform:xwiki-platform-tool-configuration-resources: check the installed version with your package manager.
- Maven org.xwiki.platform:xwiki-platform-oldcore: check the installed version with your package manager.

## Supported action
Upgrade each affected component to a fixed version on its release line. For a transitive dependency, upgrade the parent package or add an override or constraint, then regenerate the lockfile. Redeploy every environment that ran an affected version.

## Required regression checks
- Run the test suite and a production build.
- Exercise the features that depend on org.xwiki.platform:xwiki-platform-tool-configuration-resources, org.xwiki.platform:xwiki-platform-oldcore.
- Repeat the inspection and confirm that only fixed versions remain installed.

## Rollback considerations
- Keep the previous lockfile and deployment artifact. Rolling back reinstates the vulnerable version, so apply any documented mitigation while you fix forward.

## Unresolved questions
- Which deployments run an affected version?
- Exploitation status can change. Check again before lowering the priority.
- Mark the work resolved only after the fixed version is verified in production.

## Sources
- Verified: https://github.com/advisories/GHSA-9jq9-c2cv-pcrj (GitHub-reviewed advisory GHSA-9jq9-c2cv-pcrj lists affected ranges: Maven org.xwiki.platform:xwiki-platform-oldcore >=0 =13.0 =13.0 =0 <12.10.6)

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