Linux Security
16 practice questions with explanations — 15 free to try
1 of these 16 questions are in the free 15-question taster · the full topic is part of Premium
PassNova has 16 GIAC GSEC (Security Essentials) practice questions on Linux Security, each with a clear explanation. A 15-question taster is free with no sign-up; the full bank is part of PassNova Premium. Updated for 2026.
Linux Security: example questions & answers
1 worked example with answers and explanations below. Try 15 GIAC GSEC (Security Essentials) questions free in the browser; the full 16-question Linux Security bank is part of PassNova Premium.
On a modern Linux system, where are local users' password hashes stored?
- A/etc/shadow✓
- B/etc/passwd
- C/etc/group
- D/var/log/auth.log
Answer: /etc/shadow holds each account's password hash and ageing fields and is readable only by root (and, on some distributions, the shadow group). /etc/passwd is world-readable because many programs need usernames, UIDs and home directories, so its password field now holds just an 'x'. /etc/group lists groups, and /var/log/auth.log records authentication events on Debian and Ubuntu.