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Facebook uses bgsound to see if you have opened an email

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Re: Facebook uses bgsound to see if you have opened an email

#71
post #70

Earlier quoted context omitted.

It seems to be the MTA (probably the spam filter), since it happens to me even without any client open, so there's probably no way to close it by your end.

If it happens without any client open, then it isn't really a problem is it?

Well, it doesn't happen if the address doesn't exist (I tested it too), so it can still be used by spammers to check for that.

Re: Facebook uses bgsound to see if you have opened an email

#72
post #70

Earlier quoted context omitted.

If it happens without any client open, then it isn't really a problem is it?

Well, it doesn't happen if the address doesn't exist (I tested it too), so it can still be used by spammers to check for that.

If an address doesn't exist the message will simply bounce. Or am I missing something?

Re: Facebook uses bgsound to see if you have opened an email

#73
post #57

People don't expect that when they read an email, the sender knows when they read it and from what IP address. If you're using a tracking image or any similar technology, then you are exploiting a weakness in the system to take information that you don't have permission to. I recognise that it's standard industry practice, but it's categorically not ok. If you want to track users, ask for their permission. If you hav…

You are right in principle, but this isn't a tricky detail about email. This is fundamentally how Facebook and Google run their businesses.

Tracking email opens is surely helpful to their businesses, but is it really fundamental?

Re: Facebook uses bgsound to see if you have opened an email

#74

Earlier quoted context omitted.

Doesn't gmail stop these attacks without needing to force plaintext only by simply disabling images by default?

Yes. There was a bug a few years back though where they would display attached SVG images. These images could actually contain javascript, which left it vulnerable to XSS.

Why is zzz90210's post dead? Everyone knows about tracking via images. I never considered something like bgsound, probably a lot of other people did not as well.

And it's the whole point of the article.

Re: Facebook uses bgsound to see if you have opened an email

#75
post #49

Earlier quoted context omitted.

So, by the same logic, twitter should allow javascript to execute when I view some post about people microwaving small mammals. Perhaps I should be more explicit. My problem is not with the abilities to assign pixels to an output device. Email should not be an interactive proposition and should have no ability whatsoever to run code.

Email should not be an interactive proposition and should have no ability whatsoever to run code. Agreed, but HTML isn't runnable code. It's a declarative document format.

I was meaning HTML + scripting, which admittedly is much less of an issue these days. I just remember having to rescue lots of people using outlook.

Re: Facebook uses bgsound to see if you have opened an email

#77
post #64
post #38

I have yet to work out why anyone should wish to turn on html in emails ever and I always thought that was the start of email being broken. Protocols existed before machines and should serve us as well as them.

HTML isn't what bugs you. Unauthorized loading of remote content is what bugs you. That's a misfeature of your (and most people's) mail reader.

You are right, that and any ability for scripting.

Re: Facebook uses bgsound to see if you have opened an email

#78
post #62

This is yet another reason to filter all messages from Facebook directly to the trash folder. The last thing I need is a constant stream of attention-sapping fb emails polluting my inbox.

You could also just tell Facebook to not email you.

It's easier for me to setup a quick filter once than to navigate the ever-changing Facebook UI and privacy settings.

Re: Facebook uses bgsound to see if you have opened an email

#79
post #61

Earlier quoted context omitted.

The problem with attachments is that you increase the bandwidth on the sender. So, instead of, say, the sender spending 2k bandwidth per mail and each recpient another 60k on bandwidth to get images when opened, the sender pays for all that extra imagery bytes. It may shift the cost in a way you prefer, but it also slows down the send so users may not get their mails in a reasonable time, and may not appreciate the l…

The problem with attachments is that you increase the bandwidth on the sender. So, instead of, say, the sender spending 2k bandwidth per mail and each recpient another 60k on bandwidth to get images when opened, the sender pays for all that extra imagery bytes. But wouldn't the sender have to serve the images over HTTP anyway? Unless you expect a big percentage of those emails to never be opened, but then I have to w…

Yeah, not everyone opens the mail, so the recipient shouldn't have to deal with the larger download (and the sender doesn't have to send a larger mail), and also, the opens are more distributed over time (for the most part, depending on when you send and to whom), so you can send the smaller mails faster but have a more even distribution of bandwidth as the opens occur across a longer period.

Re: Facebook uses bgsound to see if you have opened an email

#80
post #72

Earlier quoted context omitted.

Well, it doesn't happen if the address doesn't exist (I tested it too), so it can still be used by spammers to check for that.

If an address doesn't exist the message will simply bounce. Or am I missing something?

Yes, here is an example of an address that doesn't exist:

https://grepular.com/email_privacy_tester/lookup?code=gapz72...

If the address exists in Gmail, you get a response on "DNS Prefetch - Anchor", so it could be used to determine whether to send an email or not. I'm not a mail administrator but I can imagine how it might be useful to a spammer, e.g to stop mass bounce replies.

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