GHSA-c5v8-2q4r-5w9v XWiki Platform Mentions UI vulnerable to Cross-site Scripting

• Maven org.xwiki.platform:xwiki-platform-mentions-ui: >= 12.5-rc-1, < 13.10.6 → fixed in 13.10.6 • Maven org.xwiki.platform:xwiki-platform-mentions-ui: >= 14.0, < 14.4 → fixed in 14.4

Impact It's possible to store Javascript or groovy scripts in an mention macro anchor or reference field. The stored code is executed by anyone visiting the page with the mention. For example, the example below will create a file at `/tmp/exploit.txt`: ``` {{mention reference="XWiki.Translation" anchor="{{/html~}~}{{async async=~"true~" cached=~"false~" context=~"doc.reference~"~}~}{{groovy~}~}new File(~"/tmp/exploit.txt~").withWriter { out -> out.println(~"owned!~"); }{{/groovy~}~}{{/async~}~}"/}} ``` Patches This issue has been patched on XWiki 14.4 and 13.10.6. Workarounds It's possible to fix the vulnerability by updating `XWiki.Mentions.MentionsMacro` and edit the `Macro code` field of the `XWiki.WikiMacroClass` XObject. ```velocity $content ``` Must be replaced by ```velocity $escapetool.xml($content) ``` See the patches: • 14.4: https://github.com/xwiki/xwiki-platform/commit/4f290d87a8355e967378a1ed6aee23a06ba162eb • 13.10.6: https://github.com/xwiki/xwiki-platform/commit/4032dc896857597efd169966dc9e2752a9fdd459#diff-4fe22885f772e47d3561a05348f73921669ec12d4413b220383b73c7ae484bc4R608-R610 References • https://jira.xwiki.org/browse/XWIKI-19752 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