The Juniper router must be configured to have Gratuitous ARP disabled on all external interfaces.
An XCCDF Rule
Description
<VulnDiscussion>A gratuitous ARP is an ARP broadcast in which the source and destination MAC addresses are the same. It is used to inform the network about a host IP address. A spoofed gratuitous ARP message can cause network mapping information to be stored incorrectly, causing network malfunction.</VulnDiscussion><FalsePositives></FalsePositives><FalseNegatives></FalseNegatives><Documentable>false</Documentable><Mitigations></Mitigations><SeverityOverrideGuidance></SeverityOverrideGuidance><PotentialImpacts></PotentialImpacts><ThirdPartyTools></ThirdPartyTools><MitigationControl></MitigationControl><Responsibility></Responsibility><IAControls></IAControls>
- ID
- SV-254032r844129_rule
- Severity
- Medium
- References
- Updated
Remediation - Manual Procedure
Disable gratuitous ARP on all external interfaces.
set interfaces <external interface> no-gratuitous-arp-reply
set interfaces <external interface> no-gratuitous-arp-request
set interfaces <external interface> unit <number> family inet address <IPv4 address>/<mask>
set interfaces <external interface> unit <number> family inet6 address <IPv6 address>/<prefix>