

Researchers have uncovered a privateness flaw in WhatsApp’s “View As soon as” characteristic, designed to reinforce person privateness by permitting media to be considered as soon as earlier than disappearing. The flaw permits attackers to simply bypass this restriction, rendering the privateness safety mechanism ineffective whereas offering customers with a false sense of safety.
Whereas the flexibility to bypass WhatsApp’s View As soon as characteristic has been identified for a while, with Chrome extensions providing this performance, a report by the Zengo X Research team that totally exposes the problem has introduced renewed concern to the WhatsApp group.
The invention was made throughout Zengo’s growth of its new multi-party computation (MPC) crypto pockets interface, Zengo Desktop. In exploring comparable mobile-first functions, the staff examined WhatsApp’s privateness options, together with “View As soon as,” and located that the characteristic’s implementation was deeply flawed, notably when used on platforms like desktop and internet, the place WhatsApp doesn’t supply full assist for it.
Zengo’s investigation revealed the next flaws in View As soon as:
- Weak API controls: The “View As soon as” restriction is meant for cell platforms, the place WhatsApp can management actions like screenshots. Nonetheless, the server API doesn’t implement these restrictions, permitting media to be downloaded on different platforms the place these controls aren’t current.
- Easy flag manipulation: “View As soon as” messages are basically common media with a flag set to restrict them to 1 view. By switching this flag from “true” to “false,” attackers can convert the message again into an everyday media file that may be saved, forwarded, or shared.
- Unauthenticated downloads: As soon as the media URL is obtained, it may be downloaded from any gadget, as no authentication is required past the decryption key.
- Delayed deletion: As a substitute of being instantly faraway from WhatsApp’s servers upon viewing, “View As soon as” media stays accessible for as much as two weeks, offering attackers with an prolonged window to use the flaw.
Zengo reviews that whereas constructing an unofficial WhatsApp shopper to reveal exploitation of the flaw, it found a number of instances of energetic exploitation within the wild, which is especially regarding for a messenger platform utilized by over 2 billion folks worldwide.


RestorePrivacy
Zengo means that WhatsApp can resolve the issue by implementing a extra strong Digital Rights Administration (DRM) system supported by {hardware} on fashionable working techniques like Android and iOS. A less complicated, although much less safe, method can be to restrict “View As soon as” media to cell (main) gadgets solely and disable it on internet and desktop platforms (companion apps).
WhatsApp’s response
WhatsApp, owned by Meta, acknowledged the problem to RestorePrivacy via an announcement from spokesperson Zade Alsawah. They confirmed that updates to the “View As soon as” characteristic are being rolled out for internet customers, they usually inspired customers to ship delicate media solely to trusted contacts.
“Our bug bounty program is a vital manner we obtain precious suggestions from exterior researchers and we’re already within the means of rolling out updates to view as soon as on internet. We proceed to encourage customers to solely ship View As soon as messages to folks they know and belief.”
WhatsApp spokesperson
WhatsApp additionally means that customers learn the Be aware part on the View As soon as’s FAQ page to higher perceive the characteristic’s sensible limitations.
Whether or not or not the fixes will affect the performance of the aforementioned Chrome extensions or unofficial shopper apps created to leverage the a number of flaws within the characteristic stays to be seen.
Till the failings in View As soon as are validated by the safety group as correctly addressed, customers needs to be cautious when counting on disappearing media options, particularly when privateness is of utmost concern. Our suggestion is that customers of any communication platform ought to by no means assume that disappearing message techniques are foolproof.
Associated: