Microsoft Exchange ProxyToken Bug May Allow Email User Theft

August 31, 2021

The details of a Microsoft Exchange Server vulnerability that allows hackers to steal email information have been disclosed.

The vulnerability – “ProxyToken” – allows hackers to send emails without authentication. Instead, the attacker makes a request to web services within the Exchange Control Panel application to gain access to messages from the victim’s inbox.

With this exploit, hackers could also forward messages intended for a target user to an account they control.

The bug was discovered and publicized last March by a researcher at the Information Security Center of Vietnam Posts and Telecommunications Group.

Since its discovery, Microsoft has announced a patch that has been available since July. The tech giant says the vulnerability is not critical, while the National Institute of Standards and Technology puts its severity score at 7.5 out of 10 because an attacker needs an account on the same Exchange server as the victim.

For more information, view the original story from Bleeping Computer.

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Jim Love

Jim is an author and podcast host with over 40 years in technology.

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