ICMP message types of interest from a remote security assessment perspective are listed in Table A-3. Both the message types and individual codes are listed, along with details of RFCs and other standards in which these message types are discussed.
Type |
Code |
Notes |
---|---|---|
0 |
0 |
Echo reply (RFC 792) |
3 |
0 |
Destination network unreachable |
3 |
1 |
Destination host unreachable |
3 |
2 |
Destination protocol unreachable |
3 |
3 |
Destination port unreachable |
3 |
4 |
Fragmentation required, but don't fragment bit was set |
3 |
5 |
Source route failed |
3 |
6 |
Destination network unknown |
3 |
7 |
Destination host unknown |
3 |
8 |
Source host isolated |
3 |
9 |
Communication with destination network is administratively prohibited |
3 |
10 |
Communication with destination host is administratively prohibited |
3 |
11 |
Destination network unreachable for type of service |
3 |
12 |
Destination host unreachable for type of service |
3 |
13 |
Communication administratively prohibited (RFC 1812) |
3 |
14 |
Host precedence violation (RFC 1812) |
3 |
15 |
Precedence cutoff in effect (RFC 1812) |
4 |
0 |
Source quench (RFC 792) |
5 |
0 |
Redirect datagram for the network or subnet |
5 |
1 |
Redirect datagram for the host |
5 |
2 |
Redirect datagram for the type of service and network |
5 |
3 |
Redirect datagram for the type of service and host |
8 |
0 |
Echo request (RFC 792) |
9 |
0 |
Normal router advertisement (RFC 1256) |
9 |
16 |
Does not route common traffic (RFC 2002) |
11 |
0 |
Time to live (TTL) exceeded in transit (RFC 792) |
11 |
1 |
Fragment reassembly time exceeded (RFC 792) |
13 |
0 |
Timestamp request (RFC 792) |
14 |
0 |
Timestamp reply (RFC 792) |
15 |
0 |
Information request (RFC 792) |
16 |
0 |
Information reply (RFC 792) |
17 |
0 |
Address mask request (RFC 950) |
18 |
0 |
Address mask reply (RFC 950) |
30 |
0 |
Traceroute (RFC 1393) |