Snapchat is trying to make it more difficult for hackers to spam your phone number.
The photo-messaging app has rolled out a new form of captcha to prevent fake users from signing up for an account, according to TechCrunch.
See also: Snapped Lets You View and Send Snapchats on Your Mac
Rather than decoding words, new users are required to select images that contain ghosts from a grid before registration can proceed. This is what the prompt looks like:

The new form of captcha is designed to help prevent hackers from creating fake users for the purpose of exploiting Snapchat's "find friends" database. Earlier this month, that feature was used to create SnapchatDB, a database that leaked 4.6 million usernames and phone numbers.
Although Snapchat claimed it had rate-limited accounts to restrict the use of its "find friends" feature, security researchers have continued to find holes in the system.
Graham Smith, a high-school student in Dallas, Texas, shed additional light into the potential for exploiting Snapchat's "find friends" feature.
On his website, Smith describes his attempts to contact Snapchat over various security flaws with the "find friends" system. Smith said he only received a response from Snapchat after he used the exploit and SnapchatDB's database to uncover the entire phone number of company cofounder and chief technology officer Bobby Murphy. It was only after calling Murphy and leaving a message that Snapchat contacted him directly.
Although the new captcha may prevent some attempts by fake user accounts to access Snapchat, and infiltrate its "find friends" system — leaving users open to spam — Smith isn't convinced it's a solid solution.
@erikgoldman @JoshConstine I'm going to agree with Erik here. I would have finished my script to crack it if I didn't have school.— Graham Smith (@neuegram) January 22, 2014
Snapchat did not immediately respond to a request for comment.
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