Published: 24 February 2020
In Zsh before 5.8, attackers able to execute commands can regain privileges dropped by the --no-PRIVILEGED option. Zsh fails to overwrite the saved uid, so the original privileges can be restored by executing MODULE_PATH=/dir/with/module zmodload with a module that calls setuid().
reproducer in debian bug low priority since upstream considers this to be a "minor vulnerability"
affects versions prior to 5.8, so only xenial and bionic needed to be patched.
Severity score breakdown