A ncompress bugfix update has been released for CentOS 7.

CentOS-announce: CEBA-2020:2655 CentOS 7 ncompress BugFix Update

CentOS Errata and Bugfix Advisory 2020:2655

Upstream details at :   https://access.redhat.com/errata/RHBA-2020:2655

The following updated files have been uploaded and are currently
syncing to the mirrors: ( sha256sum Filename )

x86_64:
74092631979cf38a57432c514323ea5ef3bfa80af4809511a285d17d23cfda85 ncompress-4.2.4.4-3.1.el7_8.x86_64.rpm

Source:
04320bf1d8e53c84fb094ed195d8c6ee81dadb2e617d84fba288659f477203db ncompress-4.2.4.4-3.1.el7_8.src.rpm