Buffer overflow in the SnifferDecompress function in wiretap/ngsniffer.c in the DOS Sniffer file parser in Wireshark 1.10.x before 1.10.10 and 1.12.x before 1.12.1 allows remote attackers to cause a denial of service (application crash) via a crafted file that triggers writes of uncompressed bytes beyond the end of the output buffer.