PROTOCOL-ICMP -- Snort alerted on Internet Control Message Protocol (ICMP) traffic, which allows hosts to send error messages about interruptions in traffic. Administrators can use ICMP to perform diagnostics and troubleshooting, but the protocol can also be used by attackers to gain information on a network. This protocol is vulnerable to several attacks, and many administrators block it altogether, or block selective messages.
PROTOCOL-ICMP Destination Unreachable Host Unreachable
This event is generated when An ICMP Host Unreachable datagram is detected on the network. Impact: Routers will generate this message when the route to the destination host on a directly connected network is not available. This occurs when no ARP response is received from the destination network. Details: This rule generates informational events about the network. Large numbers of these messages on the network could indication routing problems, faulty routing devices, or improperly configured hosts. Ease of Attack: Numerous tools and scripts can generate these types of ICMP datagrams.
No information provided
No public information
No known false positives
Original Rule writer unknown Cisco Talos Matthew Watchinski
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