The SMTP service must not have the VRFY feature active.

From VMware vRealize Operations Manager 6.x SLES Security Technical Implementation Guide

Associated with: CCI-000382

SV-99203r1_rule The SMTP service must not have the VRFY feature active.

Vulnerability discussion

The VRFY (Verify) 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.

Check content

Use the following command to check if VRFY is disabled: # grep -v "^#" /etc/sendmail.cf |grep -i PrivacyOptions If "novrfy" is not returned, this is a finding.

Fix text

Add "novrfy" to the "PrivacyOptions" flag in the "/etc/sendmail.cf" file.

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