Details

Apache web server management includes the ability to control the number of users and user sessions that utilize an Apache web server. Limiting the number of allowed users and sessions per user is helpful in limiting risks related to several types of denial-of-service (DOS) attacks.

Although there is some latitude concerning the settings, they should follow DoD-recommended values and be configurable to allow for future DoD direction. While the DoD will specify recommended values, the values can be adjusted to accommodate the operational requirements of a given system.

Solution

Determine the location of the ‘HTTPD_ROOT’ directory and the ‘httpd.conf’ file:

# httpd -V | egrep -i ‘httpd_root|server_config_file’
-D HTTPD_ROOT=’/etc/httpd’
-D SERVER_CONFIG_FILE=’conf/httpd.conf’

Set the ‘KeepAlive’ directive to a value of ‘on’; add the directive if it does not exist.

Set the ‘MaxKeepAliveRequests’ directive to a value of ‘100’ or greater; add the directive if it does not exist.

Restart Apache: apachectl restart

Supportive Information

The following resource is also helpful.

• https://dl.dod.cyber.mil/wp-content/uploads/stigs/zip/U_Apache_Server_2-4_UNIX_Y22M01_STIG.zip

This security hardening control applies to the following category of controls within NIST 800-53: Access Control.This control applies to the following type of system Unix.

References

• 800-53|AC-10
• CAT|II
• CCI|CCI-000054
• Rule-ID|SV-214228r612240_rule
• STIG-ID|AS24-U1-000010
• STIG-Legacy|SV-102685
• STIG-Legacy|V-92597
• Vuln-ID|V-214228

Source

• Tenable.com/audits