Dkimpy tool always fails agains EML exported from Outlook

Digital Forensics
1

I installed dkimpy 1.0.5 with python 3 and I found that always it fails against EML exported from outlook because body hash is not correct.

when I sent the same message to gmail client and outlook client I found that outlook added a HTML tag

, when I remove it, the verification is done and every thing is ok.

Now I want to know how to overcome this problem, because in more long messages the difference is not only this meta tag

the wired thing that MAIL::DKIL::Verifier in perl fails from all messages!!

any ideas ?

2

This is the problem. Unfortunately, Microsoft does this for both consumer accounts and O365, breaking DKIM. In complex messages, it is challenging to roll back Microsoft’s changes to the body to get DKIM verification.

I recommend getting in touch with them and voicing your opinion–especially if you are a paying customer.

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