* gnu/packages/patches/jbig2dec-CVE-2017-7885.patch, gnu/packages/patches/jbig2dec-CVE-2017-7975.patch, gnu/packages/patches/jbig2dec-CVE-2017-7976.patch: New files. * gnu/local.mk (dist_patch_DATA): Add them. * gnu/packages/image.scm (jbig2dec)[source]: Use them.