PHP Improper Restriction of Operations within the Bounds of a Memory Buffer Vulnerability - CVE-2008-5557
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.