verify_cms_signers fails on iOS 11.3.1

[mosen]

Fails to verify detached signature X-Mdm-Signature for iOS 11.3.1

[jessepeterson]

This is interesting, is it just iOS 11.3.1 and other iOS versions are okay?

[mosen]

Just iOS in general.

[CNKCQ]

Fails too
warnning message: Invalid Signature in Mdm-Signature header

[Neustradamus]

What do you think about @gekco PR?