Check: UBTU-20-010016
Canonical Ubuntu 20.04 LTS STIG:
UBTU-20-010016
(in versions v1 r12 through v1 r1)
Title
The Ubuntu operating system default filesystem permissions must be defined in such a way that all authenticated users can read and modify only their own files. (Cat II impact)
Discussion
Setting the most restrictive default permissions ensures that when new accounts are created they do not have unnecessary access.
Check Content
Verify the Ubuntu operating system defines default permissions for all authenticated users in such a way that the user can read and modify only their own files. Verify the Ubuntu operating system defines default permissions for all authenticated users with the following command: $ grep -i "umask" /etc/login.defs UMASK 077 If the "UMASK" variable is set to "000", this is a finding with the severity raised to a CAT I. If the value of "UMASK" is not set to "077", is commented out, or is missing completely, this is a finding.
Fix Text
Configure the system to define the default permissions for all authenticated users in such a way that the user can read and modify only their own files. Edit the "UMASK" parameter in the "/etc/login.defs" file to match the example below: UMASK 077
Additional Identifiers
Rule ID: SV-238209r653802_rule
Vulnerability ID: V-238209
Group Title: SRG-OS-000480-GPOS-00228
Expert Comments
CCIs
Number | Definition |
---|---|
CCI-000366 |
The organization implements the security configuration settings. |
Controls
Number | Title |
---|---|
CM-6 |
Configuration Settings |