Denial of Service in TYPO3 Bookmark Toolbar Description The TYPO3 backend allows users to create a bookmark to a page. However, the request to create a bookmark is not verified, leading to a Denial of Service (DoS) attack. Vulnerability TYPO3 versions affected: 12.4.6 and earlier Description: The bookmark toolbar of the backend interface allows users to create a bookmark to a page. The request to create a bookmark is not verified, which can be exploited to cause a DoS attack. Impact DoS attack: Users can exploit this vulnerability to create a large number of bookmarks, causing the server to become overloaded and unavailable to legitimate users. Recommendation Update to the latest version: Ensure that the TYPO3 version is updated to the latest release to mitigate this vulnerability. Patch application: Apply any available patches for the affected version. Secure configuration: Configure the application to prevent unauthorized access and ensure that the bookmark creation process is properly validated. --- This vulnerability in the TYPO3 Bookmark Toolbar allows attackers to create a large number of bookmarks, leading to a Denial of Service attack. It affects versions of TYPO3 through 12.4.6 and can be mitigated by updating to the latest version or applying available patches.