Hacking

Facebook hack allowed to disclose email address for each FB user

A Facebook hack could have been exploited to retrieve the private email address of any user with a serious impact on the privacy.

A smart Facebook hack allowed to retrieve the private email address of any user. The issue was discovered by the hacker Tommy DeVoss who awarded with $5,000 under the Facebook Bug bounty program.

“The hack allowed me to harvest as many email addresses as I wanted from anybody on Facebook,” DeVoss said. “It didn’t matter how private you thought your email address was – I could of grabbed it.”

The expert discovered the vulnerability on Thanksgiving Day and reported it Facebook via its bug bounty program.

The issue resides in the user-generated Facebook Groups feature that allows any member to create an affinity group. The administrator of a Facebook Group could invite any Facebook member to have admin roles, the invitation is handled by Facebook and sent to the member’s Facebook Messages inbox. The invitation is also sent to the email address associated with invited member’s account. DeVoss discovered that even when users decide to keep their email address private he was able to discover it.

The expert discovered the problem when he canceled pending invitations. He switched to Facebook’s mobile view of the Page Roles tab from which he was able to view the full email addresses of anyone he wanted to cancel from becoming a Facebook Group Administrator.

“While Facebook waits for the confirmation, the user is forwarded to a Page Roles tab that includes a button to cancel the request,” he explained in a blog post.

“I noticed that when you clicked to cancel the administrator invitation on the mobile page, you were redirected to a page with the email address in the URL,” he said. “Now all you have to do is pluck the plaintext version of the confidential email address straight from the URL.”

Clicking on the remove invitation link on the mobile page, the expert was redirected to a page with the following URL:

The above URL will reveal the private email of the invited user in the parameter ‘removependinginvite_email’.

This Facebook hack could have a serious impact on the user privacy, threat actors could be interested in collecting the private email addresses to conduct a wide range of malicious activities.

“Harvesting email addresses this way contradicts Facebook’s privacy policy and could lead to targeted phishing attempts or other malicious purposes.” states the post.

[adrotate banner=”9″]

Pierluigi Paganini

(Security Affairs – Facebook hack, hacking)

 

Pierluigi Paganini

Pierluigi Paganini is member of the ENISA (European Union Agency for Network and Information Security) Threat Landscape Stakeholder Group and Cyber G7 Group, he is also a Security Evangelist, Security Analyst and Freelance Writer. Editor-in-Chief at "Cyber Defense Magazine", Pierluigi is a cyber security expert with over 20 years experience in the field, he is Certified Ethical Hacker at EC Council in London. The passion for writing and a strong belief that security is founded on sharing and awareness led Pierluigi to find the security blog "Security Affairs" recently named a Top National Security Resource for US. Pierluigi is a member of the "The Hacker News" team and he is a writer for some major publications in the field such as Cyber War Zone, ICTTF, Infosec Island, Infosec Institute, The Hacker News Magazine and for many other Security magazines. Author of the Books "The Deep Dark Web" and “Digital Virtual Currency and Bitcoin”.

Recent Posts

Cisco warns of password-spraying attacks targeting Secure Firewall devices

Cisco warns customers of password-spraying attacks that have been targeting Remote Access VPN (RAVPN) services…

3 hours ago

American fast-fashion firm Hot Topic hit by credential stuffing attacks

Hot Topic suffered credential stuffing attacks that exposed customers' personal information and partial payment data.…

7 hours ago

Cisco addressed high-severity flaws in IOS and IOS XE software

Cisco addressed multiple vulnerabilities in IOS and IOS XE software that can be exploited to…

21 hours ago

Google: China dominates government exploitation of zero-day vulnerabilities in 2023

Google's Threat Analysis Group (TAG) and Mandiant reported a surge in the number of actively…

1 day ago

Google addressed 2 Chrome zero-days demonstrated at Pwn2Own 2024

Google addressed two zero-day vulnerabilities in the Chrome web browser that have been demonstrated during…

2 days ago

INC Ransom stole 3TB of data from the National Health Service (NHS) of Scotland

The INC Ransom extortion group hacked the National Health Service (NHS) of Scotland and is threatening…

2 days ago

This website uses cookies.