A newly discovered vulnerability within WhatsApp Web and Telegram Web, online platforms for two popular messaging services, lets cybercriminals fully take over user accounts and access conversations, photos, videos, contact lists, and other shared files.
The flaw lets hackers send their victims malicious code disguised within a seemingly innocent picture. When victims click the image, attackers have access to all of their storage data and can spread the harmful file through users' contact lists.
Both WhatsApp and Telegram employ end-to-end message encryption so only the participants in a conversation can view messages. This data security measure was the source of the vulnerability. Because content was encrypted on the sender's side, the two platforms did not see the content and couldn't prevent harmful files from being sent.
Check Point researchers revealed the vulnerability and disclosed its findings to the WhatsApp and Telegram security teams on March 8. Now content will be checked pre-encryption to stop malicious files from being sent.
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