An issue was discovered in mspack/chmd.c in libmspack before 0.7alpha. There is an off-by-one error in the TOLOWER() macro for CHM decompression.
Created libmspack tracking bugs for this issue:
Affects: epel-all [bug 1610944]
Affects: fedora-all [bug 1610942]
This issue affects the versions of libmspack as shipped with Red Hat Enterprise Linux 7.
This issue has been addressed in the following products:
Red Hat Enterprise Linux 7
Via RHSA-2018:3327 https://access.redhat.com/errata/RHSA-2018:3327