There is an out-of-bounds read vulnerability in the function FlateStream::getChar() located at Stream.cc in Xpdf 4.01.01. It can, for example, be triggered by sending a crafted PDF document to the pdftoppm tool. It might allow an attacker to cause Information Disclosure or a denial of service.
https://github.com/PanguL4b/pocs/tree/master/xpdf/out-of-bounds-read-in-FlateStream__getChar