When I send someone a file, are the details (Date created / Date modified / Owner / Computer) sent as well (by default)?

Question

I have created a file asd.asd:

I want to know when I email this file directly to other people, what kind of information (Date created / Date modified / Owner / Computer) will be exposed.

I am aware that I can "Remove properties and personal information". This question is: even if I do not specifically remove properties and personal information, will they be visible to the second party that downloaded my file?

Also, is there any difference in the details if instead of emailing the file directly, I zipped it up first and email it.

You can download the file at http://qweop.com/asd.zip

(I'm not talking about .txt files, but rather files in general)

Answer 1

As mentioned in Ignacio's answer, email only contains the contents of the file. But archives are different. This is the result of unzip -ql asd.zip (which lists the file contents).

  Length      Date    Time    Name
---------  ---------- -----   ----
       23  2011-07-12 14:10   asd.txt
---------                     -------
       23                     1 file

The time I guess matches with the modified date.

Answer 2

When emailing a file, only the contents and filename will be seen, and the filename even can be faked by the email program. Since .txt files don't retain any personal information within them that wasn't typed in by the user, the other side will see nothing you don't intend them to if the file is attached directly. When placed in an archive, it is possible for the archive program itself to provide additional metadata about the file within the archive.

Answer 3

Both of the previous answers are wrong, at least regarding to Date created and Date modified, see this example extracted from a real email message source:

--_017_HE1 ...id removed... p_
Content-Type: application/json; name="options.json"
Content-Description: options.json
Content-Disposition: attachment; filename="options.json"; size=123;
        creation-date="Thu, 28 Nov 2019 12:25:05 GMT";
        modification-date="Thu, 28 Nov 2019 13:49:47 GMT"
Content-ID: <F629B ...id removed... [e-mail]>
Content-Transfer-Encoding: base64

eyJqdW ... rest of base64 file contents removed

It depends on the email client, especially the one used to send the message (it has to add the creation-date and modification-date fields) and also the one used to read the message (it has to read those fields and display them or use them in some way). Many clients don't store this field, but at least one does (Microsoft Outlook).

Of course the sending client may fake the dates or the system date could be wrong, but it's usually quite reliable.