Serious flaws have been discovered in WhatsApp

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During the Black Hat security conference held last week in Las Vegas, security researchers at Check Point discussed several flaws that they found in popular messaging app WhatsApp. The latter, as many of you probably already know, was acquired by Facebook in 2014 for a price north of $21 billion. One of the features that drive users to WhatsApp is its use of end-to-end encryption; this means that a message posted by a user cannot be read by anyone but the recipient. Even Facebook can’t see the message. But the flaws found by Check Point have some serious consequences for users.
Questions & Answers
Q.What specific types of message manipulation could a hacker perform using the identified flaws?
What specific types of message manipulation could a hacker perform using the identified flaws?
A hacker could read and change a message sent by a user. They could also attribute a message to someone other than the actual sender, or disguise a public message as a private one.
Q.When were these security issues first brought to Facebook's attention?
When were these security issues first brought to Facebook's attention?
Check Point originally discovered these three issues and pointed them out to Facebook last year. One specific problem was fixed by Facebook following this disclosure.
Q.Which of the discovered flaws have been addressed by WhatsApp?
Which of the discovered flaws have been addressed by WhatsApp?
Only one of the three flaws, where a public message could be disguised as private, has been fixed. The other two flaws concerning message alteration and false attribution remain unaddressed.
Q.What was Facebook's response when these vulnerabilities were raised?
What was Facebook's response when these vulnerabilities were raised?
Facebook stated they reviewed the issue a year ago and consider it false to suggest a vulnerability. They likened the scenario to altering email replies and expressed concern about compromising privacy.