Extbase in TYPO3 4.3.0 before 6.2.24, 7.x before 7.6.8, and 8.1.1 allows remote attackers to obtain sensitive information or possibly execute arbitrary code via a crafted Extbase action.
https://typo3.org/teams/security/security-bulletins/typo3-core/typo3-core-sa-2016-013/