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Last active August 17, 2021 10:13
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Extract everything from WannaCry
import re
import os,sys
import pefile
import struct
import zipfile
import hashlib
import StringIO
from Crypto import Random
from Crypto.PublicKey import RSA
from Crypto.Cipher import PKCS1_v1_5,AES
RSA_re = re.compile(r'RSA(1|2)')
get_urls = lambda d: map(lambda x:x.strip("\x00"),re.findall("https?://[\x1f-\x7e]{6,}\x00",d))
get_strings = lambda d: re.findall('[ -~]{3,}',d)
BTC_re = re.compile('^[13][a-km-zA-HJ-NP-Z1-9]{25,34}$')
def get_rsc(pe,pred):
def walk_rsc(d):
if pred(pe,d):
x =
return pe.get_data(x.OffsetToData,x.Size)
if not hasattr(d,'directory'): return None
for d in
r = walk_rsc(d)
if r: return r
for d in pe.DIRECTORY_ENTRY_RESOURCE.entries:
if r:return r
def rsc_pe_pred(pe,d):
return hasattr(d,'data') and pe.get_data(, 2) == 'MZ'
def rsc_zip_pred(pe,d):
return hasattr(d,'data') and pe.get_data(, 2) == 'PK'
def try_passwd(zipf,f,pw):
zp = zipfile.ZipFile(StringIO.StringIO(zipf))
ret =,'r',pw).read()
return ret
except Exception as e:
return False
class RSAKEY(object):
def __init__(self,d):
self.bin = d = 0
self.bits = 0
def get_int(self,b):
r=long(self.bin[][::-1].encode('hex'),16) += self.bits/b
return r
def unpack(self):
if self.bin[0] not in ["\x06","\x07"]:
return None
if self.bin[8:12] not in ['RSA1','RSA2']:
return None
key = {}
priv = self.bin[0] == "\x07"
self.bits,key['e'] = struct.unpack('II',self.bin[12:20]) = 20
key['n']= self.get_int(8)
if priv:
key['p1'] = self.get_int(16)
key['p2'] = self.get_int(16)
key['exp1'] = self.get_int(16)
key['exp2'] = self.get_int(16)
key['coeff'] = self.get_int(16)
key['d'] = self.get_int(8)
ko = RSA.construct((key['n'],long(key['e']),key['d']))
ko = RSA.construct((key['n'],long(key['e'])))
return ko,key
def decode_aes_key(key,data):
## stolen from
## kudos to sysopfb
cipher =
sentinel =
d = cipher.decrypt(data[::-1],sentinel)
return d
def check_hdr(bin):
return True
def handle_dropper(fpath):
pe = pefile.PE(sys.argv[1])
for s in pe.sections:
if s.Name.startswith('.data'):
urls = get_urls(s.get_data())
if urls != []:
url = urls[0]
print '[+] Kill-Switch/Sandbox check url',url
return get_rsc(pe,rsc_pe_pred)
data = open(sys.argv[1]).read()
if '__TREEID__PLACE' in data:
inner_exe = handle_dropper(sys.argv[1])
pe2= pefile.PE(data=inner_exe)
print '[+] got dropper'
drop = True
#except Exception as e:
drop= False
pe2 = pefile.PE(sys.argv[1])
#fix overlay problems
overlay_off = pe2.get_overlay()
inner_exe = open(sys.argv[1]).read()
if overlay_off != None:
inner_exe = inner_exe[:-len(overlay_off)]
print '[+] got inner loader'
inner_zip =get_rsc(pe2,rsc_zip_pred)
if inner_zip != None and inner_zip.find('PK\x05\x06') == -1:
print("Corrupted archive detected")
cfg_files = []
for s in pe2.sections:
if s.Name.startswith('.data'):
data_s = s
strings= get_strings(s.get_data())
for st in strings:
if BTC_re.match(st):
print '[+] bitcoin address', st
elif st.endswith('.wnry') or st.endswith('.wry'):
print '[*] possible configuration file', st
elif st.startswith('Global'):
print '[+] Mutex',st
# for s in cfg_files:
# try_passwd(inner_zip,s,'')
passwd = None
for s in strings:
if try_passwd(inner_zip,cfg_files[-1],s):
print '[+] zip password',s
passwd = s
for f in cfg_files:
d= try_passwd(inner_zip,f,passwd)
if d and 'onion' in d:
print '[+] Configuration file',f
urls = get_strings(d)[0]
print '[+] payment sites:\n ',
print '\n '.join(urls.split(';'))
end_dll = d
if end_dll:
off = RSA_re.finditer(inner_exe).next().start() - 8
ko,key = RSAKEY(inner_exe[off:]).unpack()
print '[+] 1st Embeded RSA key'
print ko.exportKey()
if not check_hdr(end_dll):
print '[-] wrong file...'
(_, size) = struct.unpack('<IQ', end_dll[12+256:12+256+12])
aes_key = decode_aes_key(ko,end_dll[12:256+12])
c =, AES.MODE_CBC, '\x00'*16)
if drop:
fname = 'inner.%s.exe' % hashlib.sha256(inner_exe).hexdigest()
print '[+] saving inner loader as', fname
with open('/tmp/' + fname,'w') as f:
fname = '' % hashlib.sha256(inner_zip).hexdigest()
print '[+] saving inner zip as', fname
with open('/tmp/' + fname,'w') as f:
print '[+] embeded keys:'
for g in RSA_re.finditer(core):
ko,_ = RSAKEY(core[g.start()-8:]).unpack()
print ko.exportKey()
fname = 'core.%s.dll' % hashlib.sha256(core).hexdigest()
print '[+] saving core dll as', fname
with open('/tmp/' + fname,'w') as f:
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