An issue was discovered in Exiv2 0.26. The Exiv2::Internal::PngChunk::parseTXTChunk function has a heap-based buffer over-read.
https://github.com/Exiv2/exiv2/issues/306
https://lists.debian.org/debian-lts-announce/2018/06/msg00010.html
https://lists.debian.org/debian-lts-announce/2018/10/msg00012.html
https://security.gentoo.org/glsa/201811-14