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What happens when one experiences a ping of death?

What happens when one experiences a ping of death?

PrepAway - Latest Free Exam Questions & Answers

A.
This is when an IP datagram is received with the "protocol" field in the IP header set to 1 (ICMP) and the "type" field in the ICMP header is set to 18 (Address Mask Reply).

B.
This is when an IP datagram is received with the "protocol" field in the IP header set to 1 (ICMP), the Last Fragment bit is set, and (IP offset ` 8) + (IP data length) >65535.
In other words, the IP offset (which represents the starting position of this fragment in the original packet, and which is in 8-byte units) plus the rest of the packet is greater than the maximum size for an IP packet.

C.
This is when an IP datagram is received with the "protocol" field in the IP header set to 1 (ICMP) and the source equal to destination address.

D.
This is when an the IP header is set to 1 (ICMP) and the "type" field in the ICMP header is set to 5 (Redirect).

Explanation:
A hacker can send an IP packet to a vulnerable machine such that the last fragment contains an offest where (IP offset *8) + (IP data length)>65535. This means that when the packet is reassembled, its total length is larger than the legal limit, causing buffer overruns in the machine’s OS (becouse the buffer sizes are defined only to accomodate the maximum allowed size of the packet based on RFC 791)…IDS can generally recongize such attacks by looking for packet fragments that have the IP header’s protocol field set to 1 (ICMP), the last bit set, and (IP offset *8) +(IP data length)>65535" CCIE Professional Development Network Security Principles and Practices by Saadat Malik pg 414 "Ping of Death" attacks cause systems to react in an unpredictable fashion when receiving oversized IP packets. TCP/IP allows for a maximum packet size of up to 65536 octets (1 octet = 8 bits of data), containing a minimum of 20 octets of IP header information and zero or more octets of optional information, with the rest of the packet being data. Ping of Death attacks can cause crashing, freezing, and rebooting.


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