TYPO3 before 4.1.14, 4.2.x before 4.2.13, 4.3.x before 4.3.4 and 4.4.x before 4.4.1 contains an insecure default value of the variable fileDenyPattern which could allow remote attackers to execute arbitrary code on the backend.
TYPO3 8.x before 8.7.25 and 9.x before 9.5.6 allows remote code execution because it does not properly configure the applications used for image processing, as demonstrated by ImageMagick or GraphicsMagick.