email.message: header value parser get_msg_id throws IndexError on some invalid RFC822 Message-ID

[zougloub]

Bug report

Bug description:

I was looping in my inbox and found an e-mail with a Message-ID that causes an unexpected exception to be thrown:

msgid = "<[[email protected]]>"
assert msgid.startswith("<[") and msgid.endswith("]>")
email_message = email.message.EmailMessage()
email_message["Message-ID"] = msgid # Throws IndexError

CPython versions tested on:

3.11

Operating systems tested on:

Linux

[serhiy-storchaka]

This is a duplicate of #86650.

[serhiy-storchaka]

Or #105802.

[zougloub]

Thank you @serhiy-storchaka , sorry for not finding an existing bug.

[serhiy-storchaka]

Or #94306.

You are not the only one. There are currently three open issues for the same bug.