The demangle_template_value_parm and do_hpacc_template_literal functions in cplus-dem.c in libiberty allow remote attackers to cause a denial of service (out-of-bounds read and crash) via a crafted binary.
bugzilla.redhat.com/show_bug.cgi?id=1333383
gcc.gnu.org/bugzilla/show_bug.cgi?id=70926