An interesting blog post by Kristian Kielhofer describes how a specific SPI packet can kill an Intel Gigabit ethernet card [1]. If a card is exposed to this traffic, the system has to be physically power cycled. A reboot will not recover the system.
The network card crashed whenever the value 0x32 or 0x33 was found at offset 0x47f. Kristian first noticed this happening for specific SIP packets, but in the end, it turned out that any packet with 0x32 at 0x47f caused the crash. Intel traced the problem to an EEPROM used in this specific card (82574L). There are some links in the comment to the blog suggesting that others have run into this problem before. For example, the commend: ping -p 32 -s 1110 x.x.x.x can crash an affected card remotely.
[1]http://blog.krisk.org/2013/02/packets-of-death.html
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Johannes B. Ullrich, Ph.D.
SANS Technology Institute
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