Clarify chattr +a effects

HARDENING.md

@@ -10,7 +10,8 @@ measures.
 - The default shell is **/bin/bash** and is locked in the **~/.profile** file (owner and group: root, mode: 0644), so a
   non-root user can't change this.
 
-- The default history file **~/.bash_history** is unwritable (**chattr +a**). 
+- The content of the default history file **~/.bash_history** cannot be tampered with (**chattr +a** mandates it can only
+  be opened in append mode for writing).
 
 - The **HISTFILE** variable is in **readonly mode** (see **~/.profile**), so a non-root user can't change this
 
@@ -34,4 +35,4 @@ The following files are set up with the following permissions:
 - **~/.ssh folder**: mode 0700
 - **~/.ssh/authorized_keys**: mode 0600
 - **~/.ssh/config**: mode 0600
-- **~/.vimrc**: mode: 0600
+- **~/.vimrc**: mode: 0600

tasks/hardening.yml

@@ -4,7 +4,7 @@
     path: "~{{ item.key }}/.bash_history"
   register: _users_history
 
-- name: "hardening | ensure ~{{ item.key }}/.bash_history is NOT immutable"
+- name: "hardening | ensure ~{{ item.key }}/.bash_history is NOT in append only mode"
   file:
     path: "~{{ item.key }}/.bash_history"
     attr: -a
@@ -18,7 +18,7 @@
     - _users_status == "unset" or
       _users_status == "set_bash"
 
-- name: "hardening | ensure ~{{ item.key }}/.bash_history is immutable"
+- name: "hardening | ensure ~{{ item.key }}/.bash_history content cannot be tampered with"
   file:
     path: "~{{ item.key }}/.bash_history"
     attr: a