CVE-2018-7549: Canonical Ubuntu Linux

High severity, CVSS 7.5. EPSS: 2.6% chance of exploitation in the next 30 days.

In params.c in zsh through 5.4.2, there is a crash during a copy of an empty hash table, as demonstrated by typeset -p.

Affected products

• Canonical Ubuntu Linux: version 14.04 only; version 16.04 only; version 17.10 only
• Red Hat Enterprise Linux Desktop: version 7.0 only
• Red Hat Enterprise Linux Server: version 7.0 only
• Red Hat Enterprise Linux Workstation: version 7.0 only
• Zsh Zsh: up to and including 5.4.2

Published 2018-02-27. Last modified 2026-06-17.