chmextract.c in the chmextract sample program, as distributed with libmspack before 0.8alpha, does not protect against absolute/relative pathnames in CHM files, leading to Directory Traversal. NOTE: the vendor disputes that this is a libmspack vulnerability, because chmextract.c was only intended as a source-code example, not a supported application
https://www.openwall.com/lists/oss-security/2018/10/22/1
https://security.gentoo.org/glsa/201903-20
https://github.com/kyz/libmspack/commit/7cadd489698be117c47efcadd742651594429e6d