Integer underflow in the png_check_keyword function in pngwutil.c in libpng 0.90 through 0.99, 1.0.x before 1.0.66, 1.1.x and 1.2.x before 1.2.56, 1.3.x and 1.4.x before 1.4.19, and 1.5.x before 1.5.26 allows remote attackers to have unspecified impact via a space character as a keyword in a PNG image, which triggers an out-of-bounds read.
https://security.gentoo.org/glsa/201611-08
https://access.redhat.com/errata/RHSA-2016:1430
http://www.securityfocus.com/bid/80592
http://www.oracle.com/technetwork/topics/security/bulletinjul2016-3090568.html
http://www.openwall.com/lists/oss-security/2015/12/17/10
http://www.openwall.com/lists/oss-security/2015/12/11/2
http://www.openwall.com/lists/oss-security/2015/12/11/1
http://www.openwall.com/lists/oss-security/2015/12/10/7
http://www.openwall.com/lists/oss-security/2015/12/10/6
http://www.debian.org/security/2016/dsa-3443
http://sourceforge.net/projects/libpng/files/libpng15/1.5.26/
http://sourceforge.net/projects/libpng/files/libpng14/1.4.19/
http://sourceforge.net/projects/libpng/files/libpng12/1.2.56/
http://sourceforge.net/projects/libpng/files/libpng10/1.0.66/
http://sourceforge.net/p/libpng/code/ci/d9006f683c641793252d92254a75ae9b815b42ed/
http://sourceforge.net/p/libpng/bugs/244/
http://lists.fedoraproject.org/pipermail/package-announce/2015-December/174435.html