When WhatsApp allowed users to disable the ‘last seen at’ feature on its app some years ago, it was hailed as a great move. While privacy is a contentious issue in the internet world, commentators said that WhatsApp was trying its best to please those who didn’t want to share every bit of their activity on the app. However, reports have now emerged that a technical flaw on the app can allow hackers to secure details of users’ sleeping patterns depending on when they were seen ‘online’.
While WhatsApp has an option to show your ‘last seen at’ status to either everyone or only your contacts or no one, it doesn’t allow users to hide their ‘online’ status — something that Google allows in Hangouts. Hence, anybody can monitor when the user is online. Hackers can even reveal who you are talking to most, according to reports. The flaw was discovered by security researcher Rob Heaton who claimed that only a few lines of JavaScript code is required to expose user details. 
Heaton tweeted about his findings.
He explained that by using a Chrome extension he could log every time a contact was using WhatsApp and then correlate that data with other uses. His efforts indicate that if two contacts popped up at the same time, it was likely they were messaging each other. Thus, allowing hackers to know who what your most frequent chats are. “The plan is simple. Every 10 seconds, you check your target’s WhatsApp status, and note if they are online or not,” Heaton explained in a blog post titled ‘Tracking friends and strangers using WhatsApp’. 
The downside of this development is that if the few lines of code are so simple to write, it could well be managed by common people. And they’d be urged to misuse WhatsApp’s flaws to snoop into people. Businesses and personal services providers could also gain access to the private lives of people and leverage them. While that is a far-fetched thought right now, it is not impossible. It is not clear how WhatsApp, which has over a billion users, plans to correct this flaw.
{BGR}