A remote code execution vulnerability exists in the way that the Windows Graphics Device Interface (GDI) handles objects in the memory, aka 'GDI+ Remote Code Execution Vulnerability'.
https://www.zerodayinitiative.com/advisories/ZDI-19-363/
https://www.zerodayinitiative.com/advisories/ZDI-19-362/
https://portal.msrc.microsoft.com/en-US/security-guidance/advisory/CVE-2019-0853