Title

The system and user default umask must be 077. (Cat II impact)

Discussion

The umask controls the default access mode assigned to newly created files. An umask of 077 limits new files to mode 700 or less permissive. Although umask can be represented as a 4-digit number, the first digit representing special access modes is typically ignored or required to be 0. This requirement applies to the globally configured system defaults and the user defaults for each account on the system.

Check Content

Check global initialization files for the configured umask value. # grep umask /etc/* | grep -v ":#" | grep "umask [0-9]" Check local initialization files for the configured umask value. Procedure: # grep umask /userhomedirectory/.* If the system and user default umask is not 077, this is a finding. NOTE: If the default umask is 000 or allows for the creation of world-writable files this becomes a Severity Code I (CAT I) finding.

Fix Text

Edit local and global initialization files containing umask and change them to use 077 instead of the current value.

Additional Identifiers

Rule ID: SV-38475r1_rule

Vulnerability ID: V-808

Group Title: GEN002560

Expert Comments

CCIs tied to check.

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