A use-after-free flaw has been discovered in libcomps before version 0.1.10 in the way ObjMRTrees are merged. An attacker, who is able to make an application read a crafted comps XML file, may be able to crash the application or execute malicious code.
https://github.com/rpm-software-management/libcomps/issues/41
https://github.com/rpm-software-management/libcomps/commit/e3a5d056633677959ad924a51758876d415e7046
https://bugzilla.redhat.com/show_bug.cgi?id=CVE-2019-3817