Hackers abusing Dropbox to access Gmail?!!!

[gebruikersnaam]

Google Chrome is up-to-date
Versie 75.0.3770.100 (Officiële build) (32-bits)
I sent the Chrome team this 2 days ago and I also contacted API Support team...

Copy-paste:

Somehow the virus contained in this file [link removed by moderator] and this file [link removed by moderator]  immediately broke out of my 360 TotalSecurity Sandbox and not only that, it started adding all my logged in gmail accounts to dropbox!!! IP History shows a browser used in Sweden. I have 2FA enabled for all gmail accounts (no mobile number) so it's beyond me how they can add my gmail accounts (even Apps for your Domain) to Dropbox (without Dropbox being able to find the account through password reset). I quickly noticed the file was not safe so I disconnected the internet and cleaned up (only 1 PuP file for some Russian mail app in AppData\Local). Yet within 20 seconds the damage was already done... ;-(

1. how can dropbox give gmail accounts access to non-existing accounts (I got almost a dozen notification emails from Google, they are legit),
2. how can a virus read my logged in gmail addresses (I don't store any passwords but I do use lastpass, which wasn't the leak because that contains many more gmail accounts that didn't get breached)?
3. Next to the dropbox warnings, I also got a password reset email from Bittrex crypto exchange... I made that account last week, with a non-existing email address (but catch-all of my domain)... How the frack did they get that email address that quickly?
4. WHAT INFORMATION IN MY Gmail CAN BE ACCESSED THROUGH DROPBOX???!!!

Luckily I investigated the Google Notifications on my Mobile phone and immediately changed all passwords... Yet I have no idea if my private information has been stolen already... Access to my gmail would be a hackers' paradise. So far, all is good BUT I have not forgotten the password reset request for my virgin Bittrex account...!

(end copy-paste)

I thought you should know to. I have ran Avast (it was installed), 360 TotalSecurity (with all engines enabled, even Avira's) and now also a Full working Demo version of Dr.Web (which did wonders on my Android phones) including a firewall. All is (reportedly) clean.

Kindly advise: especially question 4 (ALL CAPS) is important to ME. What's going on here??? How can hackers in Sweden use Dropbox with non-existing Dropbox accounts to access my gmail??? And WHAT can they access?

Regards

* actually, the downloaders itself are kind-of safe; the resulting download (an ISO file) contains the nasty piece of software that triggered all of Google's emails warning me about Dropbox access from Sweden (where I don't live).

[Daphne]

Hey there @gebruikersnaam, I’m sorry to hear you experienced this!

Just to ensure that I understand the situation clearly, can you please clarify for me the role of Dropbox in this for me. From what I understood, Dropbox accounts were created with your Gmail email addresses, is that right?

When creating a Dropbox account, you can create it under any email address (so be careful of typos). However, to be able to use the features of Dropbox you will need access to the email address the account was created under to verify the account. Were the notifications you received about getting started and verifying the email address?

In terms of what Gmail info can be accessed through a Dropbox account, without verifying the account you wouldn’t be able to access anything. If the account had been verified and the Gmail account connected through the connected apps (which you would see from the account settings), then through Dropbox, contacts and calendars could be accessed. 

Essentially, it wouldn’t be possible to access your Gmail account by creating a Dropbox account under that email address.

I hope this hits the mark but please let me know if there is anything I’ve misunderstood or you would like some further clarification on. I’d be more than happy to assist you with this.

Thanks!

[gebruikersnaam]

Email sent by Google:

Dropbox was granted access to your Google Account

email-address@gmail.com

If you did not grant access, you should check this activity and secure your account.

Check activity

You received this email to let you know about important changes to your Google Account and services.

© 2019 Google LLC, 1600 Amphitheatre Parkway, Mountain View, CA 94043, USA

[gebruikersnaam]

Q: "Were the notifications you received about getting started and verifying the email address?"

No. No sign-up emails were received, just the above ones. A password reset for the compromised email addresses for which I got the Google warnings, did not get a password reset email from Dropbox. Google Account activity clearly shows activity from a browser session in Sweden, on ALL affected accounts.

Dropbox connected to your account

June 28, 2019 at 1:17 PM

Dropbox was granted permission to connect to your Google Account

Device:	Windows
Time:	June 28, 1:17 PM
Location:	Sweden
IP address:	185.236.42.111 

Map data ©2019

Terms of Use

Approximate location (may include nearby towns)

[Daphne]

Hey @gebruikersnaam,

Thanks for providing that info for me. At this point, it would be best to continue this discussion over on our Support channel due to the nature of the issue. Would you mind if I reached out to the email address associated with your Community profile?

Let me know - Thanks!

[gebruikersnaam]

Weird! I'm pretty sure I already replied... Yeah, sure, you may contact me. 

🙂

[Daphne]

Upon going to reach out to your email address, I located your open ticket and I’ve followed up there @gebruikersnaam. Please check your inbox at your earliest convenience for my reply.

Cheers!

[issue_goggle]

Hi,

want to know your reply as far as had same issue and hacking attamt to my google account described above. 

Absolutely same situation and recived notification email about 'Dropbox was granted access to your Google Account' and i do not have dropbox account at all.

As far as you didn't reply here need to ask to reply for myself as well

Thanks 

[Daphne]

Hey there @issue_goggle, thanks for joining us here!

I'm sorry to hear about your situation, I'll try my best to assist you with this.

Firstly, can you just check that the email you received is from an official domain? When viewing the notification you mentioned in your email inbox, you can click the sender's name to see the exact email this was sent from. What do you see there?

Also, to connect a Dropbox account to your Google account, they need to be under the same email address. Can you try signing into Dropbox with your Google email address? You can request a password reset to access the account if you need to.

Let me know what you find and we'll take it from there!

[issue_goggle]

Regarding forat question - email sender is Google  with @accounts.google.com domain

Ablout signing in into dropbox seems that no account for my google email registered but in google account in recent events I see 'Dropbox connected to your account' notification (from location far from me)