CVE-2023-40573
XWiki Platform's Groovy jobs check the wrong author, allowing remote code execution
Description
### Impact XWiki supports scheduled jobs that contain Groovy scripts. Currently, the job checks the content author of the job for programming right. However, modifying or adding a job script to a document doesn't modify the content author. Together with a CSRF vulnerability in the job scheduler, this can be exploited for remote code execution by an attacker with edit right on the wiki. For successful exploitation, the needs to have edit right on a document whose content has last been changed by a user with programming right. This could be the user profile for users created by admins. In this document, the attacker can create an object of class `XWiki.SchedulerJobClass` using the object editor. By setting job class to `com.xpn.xwiki.plugin.scheduler.GroovyJob`, cron expression to `0 0/5 * * * ?` and job script to `services.logging.getLogger("foo").error("Job content executed")`, the attacker can create a job. Now this job just needs to be triggered or scheduled. This can be achieved by embedding an image with the following XWiki syntax in any document that is visited by an admin: `[[image:path:/xwiki/bin/view/Scheduler/?do=trigger&which=Attacker.Document]]` where `Attacker.Document` is the document that has been prepared by the attacker. If the attack is successful, an error log entry with "Job content executed" will be produced. ### Patches This vulnerability has been patched in XWiki 14.10.9 and 15.4RC1. ### Workarounds There is no workaround. ### References * https://jira.xwiki.org/browse/XWIKI-20852 * https://github.com/xwiki/xwiki-platform/commit/fcdcfed3fe2e8a3cad66ae0610795a2d58ab9662
How to fix CVE-2023-40573
To remediate CVE-2023-40573, upgrade the affected package to a fixed version below.
- —no fix listed
- —upgrade to 14.10.9 or later
Is CVE-2023-40573 being exploited?
Low — EPSS is 3.6%, meaning exploitation activity has not been observed at scale.