CVE-2018-18586: Kyzer Libmspack

Medium severity, CVSS 5.3. EPSS: 3.3% chance of exploitation in the next 30 days.

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

Affected products

• Kyzer Libmspack: version 0.3 only; version 0.4 only; version 0.5 only; version 0.6 only; version 0.7 only

Published 2018-10-23. Last modified 2026-06-17.