The SLES for vRealize must protect against or limit the effects of Denial of Service (DoS) attacks by ensuring the SLES for vRealize is implementing rate-limiting measures on impacted network interfaces.

Overview

Finding ID	Version	Rule ID	IA Controls	Severity
V-89811	VRAU-SL-001305	SV-100461r1_rule		High

Description
DoS is a condition when a resource is not available for legitimate users. When this occurs, the organization either cannot accomplish its mission or must operate at degraded capacity. This requirement addresses the configuration of the operating system to mitigate the impact of DoS attacks that have occurred or are ongoing on system availability. For each system, known and potential DoS attacks must be identified and solutions for each type implemented. A variety of technologies exist to limit or, in some cases, eliminate the effects of DoS attacks (e.g., limiting processes or establishing memory partitions). Employing increased capacity and bandwidth, combined with service redundancy, may reduce the susceptibility to some DoS attacks.

Description

DoS is a condition when a resource is not available for legitimate users. When this occurs, the organization either cannot accomplish its mission or must operate at degraded capacity. This requirement addresses the configuration of the operating system to mitigate the impact of DoS attacks that have occurred or are ongoing on system availability. For each system, known and potential DoS attacks must be identified and solutions for each type implemented. A variety of technologies exist to limit or, in some cases, eliminate the effects of DoS attacks (e.g., limiting processes or establishing memory partitions). Employing increased capacity and bandwidth, combined with service redundancy, may reduce the susceptibility to some DoS attacks.

STIG	Date
VMware vRealize Automation 7.x SLES Security Technical Implementation Guide	2018-10-12

Details

Check Text ( C-89503r1_chk )
Check that the system configured to use TCP syncookies when experiencing a TCP SYN flood. # cat /proc/sys/net/ipv4/tcp_syncookies If the result is not "1", this is a finding.

Fix Text (F-96553r1_fix)
Configure the system to use TCP syncookies when experiencing a TCP SYN flood. Check for the presence of "net.ipv4.tcp_syncookies" in the /etc/sysctl.conf file: # grep "net.ipv4.tcp_syncookies" /etc/sysctl.conf If it exists, change the value to "1". If it does not exist, add a setting for tcp_syncookies: # echo "net.ipv4.tcp_syncookies=1" >> /etc/sysctl.conf Reload sysctl to verify the new change: # sysctl -p

Fix Text (F-96553r1_fix)

Configure the system to use TCP syncookies when experiencing a TCP SYN flood.

Check for the presence of "net.ipv4.tcp_syncookies" in the /etc/sysctl.conf file:

# grep "net.ipv4.tcp_syncookies" /etc/sysctl.conf

If it exists, change the value to "1". If it does not exist, add a setting for tcp_syncookies:

# echo "net.ipv4.tcp_syncookies=1" >> /etc/sysctl.conf

Reload sysctl to verify the new change:

# sysctl -p