TYPO3-CORE-SA-2020-012: XML External Entity in Dashboard Widget

Categories: Development, TYPO3 CMS Created by Oliver Hader
It has been discovered that TYPO3 CMS is susceptible to XML external entity processing.

Problem Description

It has been discovered that RSS widgets are susceptible to XML external entity processing.
This vulnerability is reasonable, but is theoretical - it was not possible to actually reproduce the vulnerability with current PHP versions of supported and maintained system distributions.

At least with libxml2 version 2.9, the processing of XML external entities is disabled per default - and cannot be exploited. Besides that, a valid backend user account is needed.

Solution

Update to TYPO3 version 10.4.10 that fixes the problem described.

Credits

Thanks to Victoria Lee who reported this issue and to TYPO3 security team member Oliver Hader who fixed the issue.

General Advice

Follow the recommendations that are given in the TYPO3 Security Guide. Please subscribe to the typo3-announce mailing list.

General Note

All security related code changes are tagged so that you can easily look them up in our review system.