| # CIS 5.4.4 Ensure default user umask is 027 or more restrictive (Scored) |
| # |
| # Description |
| # =========== |
| # The default umask determines the permissions of files created by users. |
| # The user creating the file has the discretion of making their files and |
| # directories readable by others via the chmod command. Users who wish to |
| # allow their files and directories to be readable by others by default may |
| # choose a different default umask by inserting the umask command into the |
| # standard shell configuration files ( .profile , .bashrc , etc.) in their |
| # home directories. |
| # |
| # Rationale |
| # ========= |
| # Setting a very secure default value for umask ensures that users make a |
| # conscious choice about their file permissions. A default umask setting of |
| # 077 causes files and directories created by users to not be readable by |
| # any other user on the system. A umask of 027 would make files and |
| # directories readable by users in the same Unix group, while a umask of 022 |
| # would make files readable by every user on the system. |
| # |
| # Audit |
| # ===== |
| # Run the following commands and verify all umask lines returned are 027 or |
| # more restrictive. |
| # |
| # # grep "^umask" /etc/bash.bashrc |
| # umask 027 |
| # # grep "^umask" /etc/profile |
| # umask 027 |
| # |
| # Remediation |
| # =========== |
| # Edit the /etc/bash.bashrc and /etc/profile files (and the appropriate files |
| # for any other shell supported on your system) and add or edit any umask |
| # parameters as follows: |
| # |
| # umask 027 |
| # |
| # Notes |
| # ===== |
| # The audit and remediation in this recommendation apply to bash and shell. |
| # If other shells are supported on the system, it is recommended that their |
| # configuration files also are checked. |
| # |
| # Other methods of setting a default user umask exist however the shell |
| # configuration files are the last run and will override other settings if |
| # they exist therefore our recommendation is to configure in the shell |
| # configuration files. If other methods are in use in your environment they |
| # should be audited and the shell configs should be verified to not override. |
| # |
| parameters: |
| linux: |
| system: |
| shell: |
| umask: "027" |
| |