Rule ID
SV-237051r831326_rule
Version
V2R2
CCIs
CCI-002385
If the network does not provide safeguards against DoS attacks, network resources will be unavailable to users. Installation of content filtering gateways and application layer firewalls at key boundaries in the architecture mitigates the risk of DoS attacks. These attacks can be detected by matching observed communications traffic with patterns of known attacks and monitoring for anomalies in traffic volume, type, or protocol usage. Detection components that use signatures can detect known attacks by using known attack signatures. Signatures are usually obtained from and updated by the vendor.
Review the device configuration. The following command displays the device configuration and filters the output on the string "anomaly-drop": show run | inc anomaly-drop The output should display the following commands: ip anomaly-drop ip-option ip anomaly-drop land-attack ip anomaly-drop ping-of-death ip anomaly-drop frag ip anomaly-drop tcp-no-flag ip anomaly-drop tcp-syn-fin ip anomaly-drop tcp-syn-frag ip anomaly-drop out-of-sequence [threshold] ip anomaly-drop ping-of-death ip anomaly-drop zero-window [threshold] ip anomaly-drop bad-content If the output does not show these commands, this is a finding.
The following commands configure DDoS filters: ip anomaly-drop ip-option ip anomaly-drop land-attack ip anomaly-drop ping-of-death ip anomaly-drop frag ip anomaly-drop tcp-no-flag ip anomaly-drop tcp-syn-fin ip anomaly-drop tcp-syn-frag ip anomaly-drop out-of-sequence [threshold] ip anomaly-drop ping-of-death ip anomaly-drop zero-window [threshold] ip anomaly-drop bad-content Note: Thresholds are specific to the expected traffic for the system or enclave.