Dridex – Password Bypass, Extracting Macros, and Rot13

When attackers decide to password protect something, it can be very frustrating as an analyst, because we are often left with few options to find out what they are protecting. If this happens, we can always try to straight up brute force the password, but unless the attackers use something like 1q2w3e4r, we’re up a creek without an oar. If it’s an MD5 hash of a password, we have many more options to crack it. In the case of xls files, we have the option to essentially “wipe out” the password and give it our own password. In a recent wave of Dridex phishing emails, this is what we saw. Here’s the phishing email sent to one PhishMe employee: