Check: WA000-WWA028 A24
Apache Server 2.4 Unix:
WA000-WWA028 A24
(in version v1 r1)
Title
The httpd.conf MinSpareServers directive must be set properly. (Cat II impact)
Discussion
These requirements are set to mitigate the effects of several types of denial of service attacks. Although there is some latitude concerning the settings themselves, the requirements attempt to provide reasonable limits for the protection of the web server. If necessary, these limits can be adjusted to accommodate the operational requirement of a given system. From Apache.org: The MinSpareServers directive sets the desired minimum number of idle child server processes. An idle process is one which is not handling a request. If there are fewer than MinSpareServers idle, then the parent process creates new children: It will spawn one, wait a second, then spawn two, wait a second, then spawn four, and it will continue exponentially until it is spawning 32 children per second. It will stop whenever it satisfies the MinSpareServers setting. Tuning of this parameter should only be necessary on very busy sites. Setting this parameter to a large number is almost always a bad idea.
Check Content
To view the MinSpareServers value enter the following command: find / -name httpd.conf -print -exec grep -H -i "MinSpareServers" {} \; If the value of "MinSpareServers" is not between 5 and 10, this is a finding. If the directive does not exist, this is NOT a finding because it will default to 5. It is recommended that the directive be explicitly set to prevent unexpected results if the defaults change with updated software. NOTE: This vulnerability can be documented locally with the ISSM/ISSO if the site has operational reasons for the use of increased or decreased value. If the site has this documentation, this should be marked as Not a Finding.
Fix Text
Edit the httpd.conf file and set the value of "MinSpareServers" to a value between 5 and 10, add the directive if it does not exist.
Additional Identifiers
Rule ID:
Vulnerability ID: V-13728
Group Title:
Expert Comments
CCIs
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Controls
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