A remote code execution vulnerability exists within multiple subsystems of Drupal 7.x and 8.x. This potentially allows attackers to exploit multiple attack vectors on a Drupal site, which could result in the site being compromised. This vulnerability is related to Drupal core - Highly critical - Remote Code Execution - SA-CORE-2018-002. Both SA-CORE-2018-002 and this vulnerability are being exploited in the wild.
https://www.exploit-db.com/exploits/44557/
https://www.exploit-db.com/exploits/44542/
https://www.drupal.org/sa-core-2018-004
https://www.debian.org/security/2018/dsa-4180
https://lists.debian.org/debian-lts-announce/2018/04/msg00030.html