A bug in util-print.c:relts_print() that could cause buffer overflow in multiple protocol parsers (DNS, DVMRP, HSRP, IGMP, lightweight resolver protocol, PIM) was found that may cause a segmentation fault. This issue can be be exploited either locally by making the target system to decode crafted .pcap file using tcpdump, or remotely by sending crafted packets to the network segment where the target system is running tcpdump decoding the live packet capture.
Upstream changelog:
http://www.tcpdump.org/tcpdump-changes.txt