Know every vulnerabilitybefore it knows you.
DevGuard continuously monitors your dependencies and alerts you when CVEs like this one affect your stack — with real-time threat intelligence built for developers.
GHSA-gr82-8fj2-ggc3
No affected components available
Impact
An attacker can create a template provider on any document that is part of the wiki (could be the attacker's user profile) that contains malicious code. This code is executed when this template provider is selected during document creation which can be triggered by sending the user to a URL. For the attacker, the only requirement is to have an account as by default the own user profile is editable. This allows an attacker to execute arbitrary actions with the rights of the user opening the malicious link. Depending on the rights of the user, this may allow remote code execution and full read and write access to the whole XWiki installation.
For reproduction, the following steps can be used:
- As a simple user with no script right, edit the user profile with the object editor and add an object of type "Template Provider Class". Set the name to "My Template", set template to any page on the wiki. In "Creation Restrictions", enter
<img onerror="alert(1)" src="https://www.example.com". Accept the suggestion to add this string in the dropdown. Click "Save & View" - As any user with edit right, open
<xwiki-host>/xwiki/bin/create/Main/WebHome?parent=&templateprovider=XWiki.<username>&name=foo&spaceReference=Bar, where<xwiki-host>is the URL of your XWiki installation and<username>is the username of the attacker.
If an alert is displayed, the installation is vulnerable.
Patches
This has been patched in XWiki 14.10.12 and 15.5RC1 by adding the appropriate escaping.
Workarounds
The vulnerable template file createinline.vm is part of XWiki's WAR and can be patched by manually applying the changes from the fix.
References
- https://github.com/xwiki/xwiki-platform/commit/ba56fda175156dd35035f2b8c86cbd8ef1f90c2e
- https://jira.xwiki.org/browse/XWIKI-20962
The vulnerability can be exploited over the network without needing physical access. It is easy for an attacker to exploit this vulnerability. An attacker needs basic access or low-level privileges. The attacker needs the user to perform some action, like clicking a link. The vulnerability can affect other systems as well, not just the initial system. There is a high impact on the confidentiality of the information. There is a high impact on the integrity of the data. There is a high impact on the availability of the system.
Exploitation activity has been observed. Apply available patches or mitigations urgently.
The exploit probability is very low. The vulnerability is unlikely to be exploited in the next 30 days.
We did not find any exploit available. Neither in GitHub repositories nor in the Exploit-Database.
Browse More
Continuously monitor your dependencies and get alerted when vulnerabilities like this one affect your stack.
Checkout DevGuard