An issue was discovered in Adobe Acrobat and Reader: 2017.012.20098 and earlier versions, 2017.011.30066 and earlier versions, 2015.006.30355 and earlier versions, and 11.0.22 and earlier versions. This vulnerability leads to a stack-based buffer overflow condition in the internal Unicode string manipulation module. It is triggered by an invalid PDF file, where a crafted Unicode string causes an out of bounds memory access of a stack allocated buffer, due to improper checks when manipulating an offset of a pointer to the buffer. Attackers can exploit the vulnerability and achieve arbitrary code execution if they can effectively control the accessible memory.
https://helpx.adobe.com/security/products/acrobat/apsb17-36.html