|Heap-based buffer overflow in
ext/mbstring/libmbfl/filters/mbfilter_htmlent.c in the mbstring
extension in PHP 4.3.0 through 5.2.6 allows context-dependent
attackers to execute arbitrary code via a crafted string containing an
HTML entity, which is not properly handled during Unicode conversion,
related to the (1) mb_convert_encoding, (2) mb_check_encoding, (3)
mb_convert_variables, and (4) mb_parse_str functions.