If attackers have access to a user's network,
such as by sharing the same unsecured wireless service offered
by a restaurant, they could see or alter exchanges between the
user and protected sites such as Gmail and Facebook, experts
"It's as bad as you could imagine, that's all I can say," said
Johns Hopkins University cryptography professor Matthew Green.
Apple did not say when or how it learned about the flaw in the
way iOS handles sessions in what are known as secure sockets
layer or transport layer security, nor did it say whether the
flaw was being exploited.
But a statement on its support website was blunt: The software
"failed to validate the authenticity of the connection."
Apple released software patches and an update for the current
version of iOS for iPhone 4 and later, 5th-generation iPod
touches, and iPad 2 and later.
Without the fix, a hacker could impersonate a protected site and
sit in the middle as email or financial data goes between the
user and the real site, Green said.
Apple did not reply to requests for comment. The flaw appears to
be in the way that well-understood protocols were implemented,
an embarrassing lapse for a company of Apple's stature and
The company was recently stung by leaked intelligence documents
claiming that authorities had 100 percent success rate in
breaking into iPhones.
Friday's announcement suggests that enterprising hackers could
have had great success as well if they knew of the flaw.
(Reporting by Joseph Menn; editing
by Ken Wills)
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