Check: SRG-NET-000362-RTR-000114
Router SRG:
SRG-NET-000362-RTR-000114
(in versions v5 r1 through v4 r1)
Title
The router must be configured to have Internet Control Message Protocol (ICMP) mask replies disabled on all external interfaces. (Cat II impact)
Discussion
The ICMP supports IP traffic by relaying information about paths, routes, and network conditions. Routers automatically send ICMP messages under a wide variety of conditions. Mask Reply ICMP messages are commonly used by attackers for network mapping and diagnosis.
Check Content
Review the device configuration to determine if controls have been defined to ensure the router does not send ICMP Mask Reply messages out to any external interfaces. If ICMP Mask Reply messages are enabled on any external interfaces, this is a finding.
Fix Text
Disable ICMP mask replies on all external interfaces.
Additional Identifiers
Rule ID: SV-207154r856638_rule
Vulnerability ID: V-207154
Group Title: SRG-NET-000362
Expert Comments
CCIs
| Number | Definition |
|---|---|
| CCI-002385 |
Protect against or limit the effects of organization-defined types of denial-of-service events. |
Controls
| Number | Title |
|---|---|
| SC-5 |
Denial of Service Protection |