Security News > 2022 > October > FYI: Microsoft Office 365 Message Encryption relies on insecure block cipher

Microsoft Office 365 Message Encryption claims to offer a way "To send and receive encrypted email messages between people inside and outside your organization."

Office 365 Message Encryption relies on a strong cipher, AES, but WithSecure says that's irrelevant because ECB is weak and vulnerable to cryptanalysis regardless of the cipher used.

Microsoft leaves the Office, rebrands everything as 365.

Microsoft in April introduced a data governance system called Microsoft Purview.

Office 365 Message Encryption is now considered a legacy system.

"Since Microsoft has no plans to fix this vulnerability the only mitigation is to avoid using Microsoft Office 365 Message Encryption," the lab concludes.

News URL

https://go.theregister.com/feed/www.theregister.com/2022/10/14/microsoft_office_365_message_encryption/