Citi iPhone banking app contains security flaw

iPhone-owning customers of Citigroup have been urged to update their mobile banking app immediately because of a security flaw that secretly stored account numbers, bill payments and security access codes in a hidden file.

The Citi Mobile app allows customers to check their account balances, transfer funds and pay bills from their iPhone, and is one of the most popular finance applications in the Apple App Store with approximately 120,000 users since it was launched in March 2009.

Citigroup told the Wall Street Journal that it had “no reason to believe that our customers’ personal information has been accessed or used inappropriately by anyone.”

However, there will undoubtedly be concerns that if users lost their iPhone the information could be accessed by an identity thief. Furthermore, it is believed that the sensitive data could…

Read more in my article on the Naked Security website.

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Graham Cluley is a veteran of the cybersecurity industry, having worked for a number of security companies since the early 1990s when he wrote the first ever version of Dr Solomon's Anti-Virus Toolkit for Windows. Now an independent analyst, he regularly makes media appearances and is an international public speaker on the topic of cybersecurity, hackers, and online privacy. Follow him on Twitter, Mastodon, Bluesky, or drop him an email.

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