A vulnerability while parsing "application/http-index-format" format content where uninitialized values are used to create an array. This could allow the reading of uninitialized memory into the arrays affected. This vulnerability affects Thunderbird < 52.1, Firefox ESR < 45.9, Firefox ESR < 52.1, and Firefox < 53.

Stack-based buffer overflow in the evutil_parse_sockaddr_port function in evutil.c in libevent before 2.1.6-beta allows attackers to cause a denial of service (segmentation fault) via vectors involving a long string in brackets in the ip_as_string argument.