44 million Microsoft customers found using compromised passwords
The company has issued widespread password resets for those affected


Microsoft's identity threat researchers have revealed that 44 million of its users are still using passwords that have previously been compromised in past data breaches.
The 44 million weak accounts comprised both Microsoft Services Accounts (regular users) and Azure AD accounts too, suggesting businesses are not adopting proper password hygiene.
A total of three billion user credentials were checked in a database populated from numerous sources including law enforcement and public databases.
Using the data set of three billion credentials, Microsoft was able to identify the number of users who were resuing credentials across multiple online services.
Microsoft forced a password reset for all of those users who were found to have leaked credentials during the scan which took place between January and March 2019.
"On the enterprise side, Microsoft will elevate the user risk and alert the administrator so that a credential reset can be enforced," the company said.
Microsoft also said if users are going to reuse login credentials across different services, enabling a form of multi-factor authentication (MFA) is imperative.
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"MFA is an important security mechanism that can dramatically improve your security posture," it said. "Our numbers show that 99.9% of identity attacks have been thwarted by turning on MFA."
"In today's cybersecurity landscape, it couldn't be truer to say that passwords are the weakest link," said Robert Ramsden Board, VP EMEA at Securonix. "We need to create several versions of them, make them hard to guess and commit them to memory. Therefore, it comes as no surprise that password reuse is so rampant."
"Two-Factor authentication can help tackle the risk posed by password reuse," he added. "However, organisations and users should explore alternatives to the traditional text password, such as persona-based authentication."
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When individuals reuse their login details with slight modifications, it's still 'incredibly' easy to break into them, according to a 2018 Virginia Tech study.
Out of 30 million users examined, 52% used modified versions of their credentials. The researchers found that even when modified, 30% of the credentials could be guessed within 10 attempts.
Earlier this year, Microsoft raised the character limit for Azure AD accounts from 16 characters to 256 which vastly improved the security of passwords and the time it would theoretically take to brute force an account.
Google released figures earlier this year which seemed to align closely with the number of weak accounts that Microsoft scanned.
Google announced that 1.5% of all account logins use compromised passwords, according to figures from its Password Checkup Chrome extension. This is not too dissimilar to Microsoft's findings which equate to 1.46% of the total number of scanned users.

Connor Jones has been at the forefront of global cyber security news coverage for the past few years, breaking developments on major stories such as LockBit’s ransomware attack on Royal Mail International, and many others. He has also made sporadic appearances on the ITPro Podcast discussing topics from home desk setups all the way to hacking systems using prosthetic limbs. He has a master’s degree in Magazine Journalism from the University of Sheffield, and has previously written for the likes of Red Bull Esports and UNILAD tech during his career that started in 2015.
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