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Servers – Remove Legacy '+' Entries from Passwd
Support > Fixing Checks > Server
06 March, 2026
This check ensures that there are no legacy '+' entries present in the
/etc/passwd file. Historically, the '+' character was used as a marker to
include account information from Network Information Service (NIS) maps.
Modern systems no longer rely on this mechanism. If these entries remain in the system configuration files, they may allow unintended access or expose the system to security risks.
Check Details
- Resource: Server
- Check: Validate NIS Legacy Entries
-
Risk: If legacy
'+'entries exist in the/etc/passwdfile, attackers may exploit them to gain unauthorized or privileged access to the system.
Remediation Steps
- Open a terminal session on the server with root or sudo privileges.
-
Check the
/etc/passwdfile for any legacy'+'entries.grep '^\+:' /etc/passwd
-
If the command returns any output, it indicates that legacy
'+'entries exist in the file. -
Open the
/etc/passwdfile using a text editor.sudo nano /etc/passwd
-
Locate and remove any lines that begin with
'+'. - Save the file and exit the editor.
-
Run the audit command again to confirm that no legacy entries remain.
grep '^\+:' /etc/passwd
- If the command returns no output, the system is correctly configured.