Is it possible to extract Metadata from a Photo attached to an Email?
I was recently asked to answer this question whether it was possible to extract metadata from a photo attached to an email on Quora.
It is an interesting question which has an interesting answer as it possible to extract metadata from the photo. However, depending on what email client (app) was used, whether the photo was emailed via a chat app (for example: wechat, messenger etc) and the recipient’s email server as the amount of meta data obtained may vary.
You might obtain the metadata as identical to the original photo, or find it stripped (completely removed) or only able to extract some of the metadata or otherwise have new metadata added (tampered).
Metadata with Email Clients
At snapWONDERS we experienced a variation on the above where some of our users wanted to email us their photo for metadata analysis and upon receipt, we found the metadata had been tampered with. To circumvent this issue, we built an upload photo portal which permitted direct uploading of photos leaving the metadata intact.
Some of the photos we received in the original form varied in size from 2Mb to 15Mb as opposed to the photo received via the email being generally under 500Kb in size.
Some of the reasons this happens is because some email clients or email servers resize the photos and, in the process, remove or reduce the metadata. This could be done for numerous of reasons which includes protecting your privacy, minimising photo storage space at the email server end and minimising bandwidth as part of uploading the photos.
To mitigate this, you could:
- Compress the photos (with password) to prevent tampering of the photo attachments.
- Attach the photo to the email as opposed to embedding the photo within the email body (sometimes that trick works)
Testing Metadata Tampering by Email Clients
You could test to see if your Email Client is tampering with your Metadata by running the photo via snapWonders analyser to check the metadata before and after to confirm whether the metadata remains unchanged. To avoid confusion, you would probably need to start with you having the original photo with the known metadata, and send this to the person for testing and check the meta data at each stage:
- The metadata before you emailed to the person for testing
- The metadata as received from the tester
- The metadata as received by the tester emailing you back the original photo
At snapWONDERS we care about privacy and copyrights especially in relation to digital photos. If you have anything to share about hidden metadata within photos or discovered a smartphone or camera that is a privacy concern, then we would be interested in learning more. Meanwhile, snapWONDERS can automatically assess privacy and copyright concerns with digital photos online.