There is a remote denial of service exploit against tcpdump. Tcpdump interprets UDP packets on port 53 as DNS traffic, however, domain names in DNS packets use a compression scheme that jumps to a particular offset in the packet to avoid multiple occurances. Sending a packet that has the offset set to a particular location and if a program trying to decompress the domain name does not have a strategy for avoiding infinite loops, tcpdump may fall into an infinite loop.
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