Pierluigi Paganini December 28, 2013

Gibson Security revealed that The ‘Find Friends’ exploit and the ‘Bulk Registration’ Exploit menace the security and privacy of million of Snapchat users.

Gibson Security has recently published the details of a couple of SnapChat vulnerabilities which could be exploited by hackers respectively to massively disclose users and associated phone numbers, and enable the creation fake accounts.

Snapchat is a photo messaging application, the decision to publicly disclose the bug come after that the Snapshot authors have repeatedly ignored for four months the bugs reported by Gibson security.

“Given that it’s been around four months since our last Snapchat release, we figured we’d do a refresher on the latest version, and see which of the released exploits had been fixed (full disclosure: none of them). Seeing that nothing had been really been improved upon (although, stories are using AES/CBC rather than AES/ECB, which is a start), we decided that it was in everyone’s best interests for us to post a full disclosure of everything we’ve found in our past months of hacking the gibson. In the time since our previous release, there have been numerous public Snapchat api clients created on GitHub. Thankfully, Snapchat are too busy declining ridiculously high offers from Facebook and Google, and lying to investors (hint: they have no way to tell the genders of their users, see /bq/register for a lack of gender specification) to send unlawful code takedown requests to all the developers involved.”

The researchers demonstrated that using a script (dubbed “find_friends” exploit) invoking API of Snapchat they are able to associate phone numbers with users’ nickname, user names and account privacy level. It’s clears that users of Snapchat are exposed to risk of frauds, their data could be sold and their privacy is seriously menaced.

“In an entire month, you could crunch through as many as 292 million numbers with a single server ((ncpm*60)*730, approximately 730 hours in a month). Add more servers (or otherwise increase your number crunching capabilities) and you can get through a seemingly infinite amount of numbers.” reported Gibson.

Attackers could in fact access to full social media profiles including phone numbers even if user’s account is set to private.

The second exploit proposed by the researcher is also very dangerous, it could allow anyone to create account with simple requests: “/bq/register” and “/ph/registeru.”, fraudsters could create an army of malicious account to spread malicious content, including spam and link to compromised servers serving malware.

If confirmed, the approach of Snapchat team is very reckless and imprudent, both bugs open the doors to illegal activities exposing users’data.

Waiting for the fix Snapchat recently announced to have implemented a rate-limited feature that allows users to view one time-limited snap a second time each day.

Pierluigi Paganini

(Security Affairs –  SnapChat, hacking)