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VBA deobfuscation - Emotet XLSM
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from oletools.olevba import VBA_Parser, TYPE_OLE, TYPE_OpenXML, TYPE_Word2003_XML, TYPE_MHTML | |
import sys | |
import re | |
vbaparser = VBA_Parser(sys.argv[1]) | |
replace_regex = r"\s*([^=]+)\s*=\s*Replace\(\s*([^,]+)\s*,\s*\"([^,]*)\"\s*,\s*\"([^,]*)\"\s*\)" | |
replace = re.compile(replace_regex, re.MULTILINE) | |
regex_url = "http(s)?://[^,\"]+" | |
url = re.compile(regex_url, re.MULTILINE) | |
if vbaparser.detect_vba_macros(): | |
urls = [] | |
for (filename, stream_path, vba_filename, vba_code) in vbaparser.extract_macros(): | |
vba_code = vba_code.replace("_\r\n", "") | |
match = replace.search(vba_code) | |
if match: | |
var_name = match.group(1) | |
str_name = match.group(2) | |
old_val = match.group(3) | |
new_val = match.group(4) | |
sentences =[] | |
for sentence in vba_code.split("\r\n"): | |
if str_name in sentence: | |
sentence = sentence.replace(old_val, new_val) | |
sentences.append(sentence) | |
deobfuscated_code = '\r\n'.join(sentences) | |
print(deobfuscated_code) | |
url_iter = url.finditer(deobfuscated_code) | |
for url_match in url_iter: | |
urls.append(url_match.group().rstrip('\\').rstrip('/')) | |
print("\r\n[ORIGINAL URLS]") | |
for url in urls: | |
print(url) | |
# defanged urls | |
print("\r\n[DEFANGED URLS]") | |
for url in urls: | |
print(url.replace(".","[.").replace(":","[:")) |
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