CVE-2023-36471
CriticalCVSS 9.0Exploitation Probability (EPSS)
Elevated risk55th percentile - higher than 55% of all known CVEs
Summary
XWiki commons had a vulnerability in HTML sanitization that allowed the use of form and input tags. An attacker could create phishing forms or inject malicious code that could be executed by an admin.
Risk Assessment
The organization may be exposed to phishing attacks and remote code execution, potentially leading to data loss or system takeover.
Recommendation
It is recommended to upgrade to XWiki version 14.10.6 or 15.2RC1. Alternatively, administrators can block unsafe tags in the `xwiki.properties` configuration file.
Original NVD description (English source)
Xwiki commons is the common modules used by other XWiki top level projects. The HTML sanitizer that is included in XWiki since version 14.6RC1 allowed form and input HTML tags. In the context of XWiki, this allows an attacker without script right to either create forms that can be used for phishing attacks or also in the context of a sheet, the attacker could add an input like `{{html}}<input type="hidden" name="content" value="{{groovy}}println("Hello from Groovy!")" />{{/html}}` that would allow remote code execution when it is submitted by an admin (the sheet is rendered as part of the edit form). The attacker would need to ensure that the edit form looks plausible, though, which can be non-trivial as without script right the attacker cannot display the regular content of the document. This has been patched in XWiki 14.10.6 and 15.2RC1 by removing the central form-related tags from the list of allowed tags. Users are advised to upgrade. As a workaround an admin can manually disallow the tags by adding `form, input, select, textarea, button` to the configuration option `xml.htmlElementSanitizer.forbidTags` in the `xwiki.properties` configuration file.