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But why can't I send people their passwords?

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11–20 of 181 posts

Re: But why can't I send people their passwords?

#11
post #5

> 7. Fine, but I still get to send users their passwords once they created them so they don’t forget them, right? Email is not a secure medium. It was never designed to be one. It’s susceptible to Man In The Middle (MITM) attacks and a slew of other issues. Also, users might have their email accounts abused or hacked into (how many people do you know who have left their GMail logged in on a public computer?). Would y…

[deleted]

Re: But why can't I send people their passwords?

#12
post #8
post #5

> 7. Fine, but I still get to send users their passwords once they created them so they don’t forget them, right? Email is not a secure medium. It was never designed to be one. It’s susceptible to Man In The Middle (MITM) attacks and a slew of other issues. Also, users might have their email accounts abused or hacked into (how many people do you know who have left their GMail logged in on a public computer?). Would y…

"Man In The Middle (MITM)" is the important bit. For example by sniffing the wireless traffic on an unencrypted wlan you can capture entire emails being sent or received, without ever compromising the account.

  - Request password reset.
  - Sniff email with reset link.
  - Go to reset link before user does and change password.

Re: But why can't I send people their passwords?

#13
post #12
post #8

Earlier quoted context omitted.

"Man In The Middle (MITM)" is the important bit. For example by sniffing the wireless traffic on an unencrypted wlan you can capture entire emails being sent or received, without ever compromising the account.

- Request password reset. - Sniff email with reset link. - Go to reset link before user does and change password.

That will work, however it will also leave the user with a clue that their account may have been compromised. It is also a noticable degree harder to pull off than simply sniffing a password being sent, due to needing to know the target's data necessary to request a reset.

Re: But why can't I send people their passwords?

#14
post #5

> 7. Fine, but I still get to send users their passwords once they created them so they don’t forget them, right? Email is not a secure medium. It was never designed to be one. It’s susceptible to Man In The Middle (MITM) attacks and a slew of other issues. Also, users might have their email accounts abused or hacked into (how many people do you know who have left their GMail logged in on a public computer?). Would y…

Another thing to consider is if your email provider's offline backups get jacked in transit would you rather your emails contain your plain text passwords or links to a password reset with expired tokens?

Re: But why can't I send people their passwords?

#15
post #6

I disagree with point 11. You shouldn't rely on someone else's service to be the way for users to access yours.

It's pretty hard not to though. You rely on your hosting provider for service and probably on a multitude of software services too. Of course you have to weigh the value of each further point of failure in your setup, but it's a tradeoff and may well be worth it.

Re: But why can't I send people their passwords?

#16
post #8
post #5

> 7. Fine, but I still get to send users their passwords once they created them so they don’t forget them, right? Email is not a secure medium. It was never designed to be one. It’s susceptible to Man In The Middle (MITM) attacks and a slew of other issues. Also, users might have their email accounts abused or hacked into (how many people do you know who have left their GMail logged in on a public computer?). Would y…

"Man In The Middle (MITM)" is the important bit. For example by sniffing the wireless traffic on an unencrypted wlan you can capture entire emails being sent or received, without ever compromising the account.

Entire clear text emails. Everyone SHOULD be using TLS wrapped email protocols. That doesn't mean they are, but gmail is https all the way and many providers now require TLS connections to the mail servers.

Still, one time use password reset links with explicit instructions and set expectations to reset the password immediately is the way to go if you're emailing anything IMO.

Re: But why can't I send people their passwords?

#18
post #5

> 7. Fine, but I still get to send users their passwords once they created them so they don’t forget them, right? Email is not a secure medium. It was never designed to be one. It’s susceptible to Man In The Middle (MITM) attacks and a slew of other issues. Also, users might have their email accounts abused or hacked into (how many people do you know who have left their GMail logged in on a public computer?). Would y…

The FAQ isn't saying that the only bad thing is that email accounts might be compromised, simply that that's one reason to not email passwords. While you're right about email comprises allowing an attacker to simply reset a password, the first few sentences are still very important.

> Email is not a secure medium. It was never designed to be one. It’s susceptible to Man In The Middle (MITM) attacks and a slew of other issues.

Email by default right not isn't encrypted. Anyone (eg, a 3-letter government agency or a malicous actor on an unencrypted wifi network) who can intercept your traffic can read that password - and you can't even tell. At least with a password reset there's the "notification" of "my password doesn't work anymore". That's mitigated by SSL/TLS, but it's still an important point to consider.

Re: But why can't I send people their passwords?

#19
post #5

> 7. Fine, but I still get to send users their passwords once they created them so they don’t forget them, right? Email is not a secure medium. It was never designed to be one. It’s susceptible to Man In The Middle (MITM) attacks and a slew of other issues. Also, users might have their email accounts abused or hacked into (how many people do you know who have left their GMail logged in on a public computer?). Would y…

If someone hacks into your email account, they can just trawl through the email archive and harvest passwords from past password reminder emails. With a temporary reset token, they have to initiate a password reset request, which you should notice: (a) you might notice the email if you have e.g. push notifications enabled, or if the attacker doesn't delete it quickly enough, and (b) your real password will suddenly stop working.

Additionally, even if your reset request is harvested via MITM, if you use a single-use reset token, and an attacker uses it before you can, you know something is up. Even if it's not single-use, your password suddenly no longer working should ring alarm bells.

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