Heap-based buffer overflow in the ensure_solid_xref function in pdf/pdf-xref.c in Artifex MuPDF 1.12.0 allows a remote attacker to potentially execute arbitrary code via a crafted PDF file, because xref subsection object numbers are unrestricted.
https://security.gentoo.org/glsa/201811-15
https://bugs.ghostscript.com/show_bug.cgi?id=698819
http://git.ghostscript.com/?p=mupdf.git%3Ba=commit%3Bh=55c3f68d638ac1263a386e0aaa004bb6e8bde731