UCF STIG Viewer Logo
Changes are coming to https://stigviewer.com. Take our survey to help us understand your usage and how we can better serve you in the future.
Take Survey

The SMTP service must not have the Verify (VRFY) feature active.


Overview

Finding ID Version Rule ID IA Controls Severity
V-4693 GEN004680 SV-37511r1_rule ECSC-1 Low
Description
The VRFY command allows an attacker to determine if an account exists on a system, providing significant assistance to a brute force attack on user accounts. VRFY may provide additional information about users on the system, such as the full names of account owners.
STIG Date
Red Hat Enterprise Linux 5 Security Technical Implementation Guide 2015-09-03

Details

Check Text ( None )
None
Fix Text (F-31422r1_fix)
Add the "novrfy" flag to your sendmail in /etc/mail/sendmail.cf.

Procedure:
Edit the definition of "confPRIVACY_FLAGS" in /etc/mail/sendmail.mc to include "novrfy".

Rebuild the sendmail.cf file with:
# make -C /etc/mail

Restart the sendmail service.
# service sendmail restart