Hotmail Password Reset Bug Exploited in Wild

UPDATE: Microsoft has issued a temporary permanent fix for a previously undisclosed bug in its MSN Hotmail Web email service that could have allowed remote attackers to reset account passwords.

UPDATE: Microsoft has issued a temporary permanent fix for a previously undisclosed bug in its MSN Hotmail Web email service that could have allowed remote attackers to reset account passwords.

The flaw in the password reset functionality allowed a remote attacker to reset the Hotmail/MSN password with their own values, according to a notice published by Vulnerability Laboratory senior researcher Benjamin Kunz Mejri. It affected Microsoft’s official MSN Hotmail (Live) service. Remote attackers could use the security hole to bypass the password recovery service to setup a new password, according to the notice.

Hotmail is the world’s largest web-based email service provider, touting some 364 million users. The flaw would also allow an attacker to bypass MSN Hotmail’s token-based login protection. According to the Vulnerability Laboratory report, the token protection only checks if input values are empty before blocking or closing the web session. Mejri managed to bypass that feature by entering a string of characters, in this case, ‘+++)-.’

“On Friday, we addressed an incident with password reset functionality; there is no action for customers, as they are protected,” a Microsoft spokesperson told Threatpost via email.

According to a report published on WhiteC0de, the exploit was initially discovered by a Saudi Arabian hacker working for Dev-point.com and was, leaked to hacker forums, where it spread quickly. Despite the quick action to fix the flaw, Whitec0de claims it has been widely used to compromise Hotmail accounts. In turn, unauthorized access to those email accounts was leveraged to gain access to social media, financial, and other accounts linked to those addresses.

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Discussion

  • Rob on

    I think there's another flaw besides this one. My hotmail account was compromised the other day, but the password was not reset.

     

  • Anonymous on

    Yes I think another bug as well. When I went to send a message a puzzle type piece, black and looking like a pirate appeared. Weird.. But my password was not changed either!

  • Anonymous on

    I never realised Hotmail was still the largest email provider. I thought Gmail took over a long time ago.

    On a slight side note, you have an error: "and was, lleaked to hacker forums". It should read "...leaked...".

  • Anonymous on

    The above comment was for Rob

  • Anonymous on

    It's hackforums, not hacker forums. Get it right please 

    -ace6697

  • Anonymous on

    mamamamamam this is bad it hack me by a 5 year old baby

     

  • Anonymous on

    recovery my password

     

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