The time you asked for follow-up drinks with the human of your dreams over WhatsApp and got rejected? Sigh. Though you’ve done your best to erase all traces of the memory, deleting the conversation and poisoning the relevant part of your brain with alcohol, that embarrassing exchange lives on somewhere in the labyrinth of WhatsApp’s systems.
iOS researcher Jonathan Zdziarski has revealed that the app stores a ‘forensic trace’ of all of your messages, even after you’ve deleted them. That means a hacker with physical access to your phone has the means of exposing all of your hidden secrets.
“I installed the app and started a few different threads,” he wrote. “I then archived some, cleared, some, and deleted some threads. I made a second backup after running the ‘Clear All Chats’ function in WhatsApp. None of these deletion or archival options made any difference in how deleted records were preserved. In all cases, the deleted SQLite records remained intact in the database.
“Just to be clear, WhatsApp is deleting the record (they don’t appear to be trying to intentionally preserve data), however the record itself is not being purged or erased from the database, leaving a forensic artifact that can be recovered and reconstructed back into its original form.”
However, he added that WhatsApp users shouldn’t be too alarmed by the discovery, as numerous other messaging apps leave behind similar traces, though he does recommend setting up a complex backup password for your phone.