Troublemakers with enough time on their hands, and strength in their fingers, can crash WhatsApp
by piling in 4,000 or so smiley emojis into a message and sending it along, according to an independent security researcher.
Indrajeet Bhuyan blogged that an excessive number of smileys will max out Whatsapp's character limit – first slowing down and then crashing both the mobile app and desktop version.
In whatsapp web, whatsapp allows 6,500-6,600 characters. But after typing about 4,200-4,400 smileys the browser starts to slow down. However, since the limit is not yet reached, Whatsapp allows a person to go on inserting smiley faces. This causes it to crash while we type and send. In the mobile version, when it receives the message the buffer overflows and it crashes, he wrote.
Bhuyan said he tested his theory on Firefox, Chrome, several Android versions and iOS, but with Apple the trick only froze the app and did not cause a crash.
This is the second time Bhuyan has found an issue with Whatsapp. Last year he demonstrated how a 2000 word message in a special character set could take down the app.
Whatsapp has yet to reply to an attempt by SCMagazine.com for comment on the issue.