• Release Date: August 10, 2021
  • Component Type: Third party extension. This extension is not a part of the TYPO3 default installation.
  • Component: "Deferred image processing" (deferred_image_processing)
  • Vulnerability Type: Denial of Service
  • Affected Versions: 1.0.1 and below
  • Severity: High
  • Suggested CVSS: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H/E:F/RL:O/RC:C
  • References: N/A

Problem Description

Wrong usage of the TYPO3 FAL API results in copies of processed files being saved to the /var/transient/ folder of a TYPO3 website on every frontend request. This  can result in Denial of Service, since the webspace may be filled up with image files simply by crafting a large amount of requests to the website.


An updated version 1.0.2 is available from the TYPO3 extension manager, Packagist and at


Users of the extension are advised to update the extension as soon as possible.


Thanks to Thorben Nissen for providing an updated version of the extension.

General Advice

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