Summary
It's possible to execute anything with the rights of the author of a macro which uses the {{wikimacrocontent}} macro
Workarounds
There is no easy workaround other than disabling the affected macros.
Inserting content in a safe way or knowing what is the user who called the wiki macro is not easy.
References
https://jira.xwiki.org/browse/XWIKI-17759
For more information
If you have any questions or comments about this advisory:
- Open an issue in Jira XWiki
- Email us at our security mailing list
Impact
The {{wikimacrocontent}} executes the content with the rights of the wiki macro author instead of the caller of that wiki macro. This makes possible to inject scripts through it and they will be executed with the rights of the wiki macro (very often a user which has Programming rights).
Fortunately, no such macro exists by default in XWiki Standard but one could have been created or installed with an extension.
Affected versions
Security releases
Kodem intelligence
Severity tells you how bad this could be in the worst case. It does not tell you whether you are exposed. Exploitability and impact are functions of runtime truth: whether the vulnerable code is present, reachable, and actually executes in your application. A vulnerable package can sit in your dependency tree and never run.
Kodem, an Intelligent Application Security platform, uses runtime intelligence to reveal which vulnerabilities actually execute in production, so teams prioritize the ones that genuinely matter. Kodem's runtime-powered SCA identifies whether this CVE is reachable in your applications.
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It has been patched in versions XWiki 12.6.3, 11.10.11 and 12.8-rc-1.
Frequently Asked Questions
- What is CVE-2021-21379? CVE-2021-21379 is a low-severity security vulnerability in org.xwiki.platform:xwiki-platform-rendering-wikimacro-store (maven), affecting versions >= 11.4, < 11.10.11. It is fixed in 11.10.11, 12.6.3, 12.8.
- Which versions of org.xwiki.platform:xwiki-platform-rendering-wikimacro-store are affected by CVE-2021-21379? org.xwiki.platform:xwiki-platform-rendering-wikimacro-store (maven) versions >= 11.4, < 11.10.11 is affected.
- Is there a fix for CVE-2021-21379? Yes. CVE-2021-21379 is fixed in 11.10.11, 12.6.3, 12.8. Upgrade to this version or later.
- Is CVE-2021-21379 exploitable, and should I be worried? Whether CVE-2021-21379 is exploitable in your environment depends on whether the vulnerable code is present and reachable. A CVSS score is a worst-case rating; it does not account for your specific deployment, configuration, or usage patterns. Kodem, an Intelligent Application Security platform, uses runtime intelligence to show which vulnerabilities actually execute in production, so you can focus on the ones that represent real risk. Get a demo
- What actually determines whether CVE-2021-21379 is exploitable, and how bad it is? Exploitability and impact are not fixed properties of a CVE. They depend on runtime truth: whether the vulnerable code is present, reachable, and actually executes in your application. A high CVSS score on a dependency that never runs is not the same as real risk. Kodem, an Intelligent Application Security platform, uses runtime intelligence to reveal which vulnerabilities actually execute in production, so teams prioritize the ones that genuinely matter.
- How do I fix CVE-2021-21379?
- Upgrade
org.xwiki.platform:xwiki-platform-rendering-wikimacro-storeto 11.10.11 or later - Upgrade
org.xwiki.platform:xwiki-platform-rendering-wikimacro-storeto 12.6.3 or later - Upgrade
org.xwiki.platform:xwiki-platform-rendering-wikimacro-storeto 12.8 or later
- Upgrade