The dissectstunmessage function in epan/dissectors/packet-stun.c in the STUN dissector in Wireshark 1.4.x before 1.4.15, 1.6.x before 1.6.10, and 1.8.x before 1.8.2 does not properly interact with key-destruction behavior in a certain tree library, which allows remote attackers to cause a denial of service (application crash) via a malformed packet.