TechCrunch reports that Microsoft’s Outlook.com web service has been breached for around 3 months, between January and March 2019, after “cybercriminals” managed to acquire the credentials of a customer support rep.
The credentials gave access to the email addresses, subject lines and folder names of a “limited number” of email accounts (though Microsoft is not clear how many and where), but not the actual contents of the email. Enterprise users were unaffected.
“We addressed this scheme, which affected a limited subset of consumer accounts, by disabling the compromised credentials and blocking the perpetrators’ access,” said a Microsoft spokesperson in an email.
Microsoft has notified affected users by email, which can be seen in full below:
Microsoft is committed to providing our customers with transparency. As part of maintaining this trust and commitment to you, we are informing you of a recent event that affected your Microsoft-managed email account.
We have identified that a Microsoft support agent’s credentials were compromised, enabling individuals outside Microsoft to access information within your Microsoft email account. This unauthorized access could have allowed unauthorized parties to access and/or view information related to your email account (such as your e-mail address, folder names, the subject lines of e-mails, and the names of other e-mail addresses you communicate with), but not the content of any e-mails or attachments, between January 1st2019 and March 28th 2019.
Upon awareness of this issue, Microsoft immediately disabled the compromised credentials, prohibiting their use for any further unauthorized access. Our data indicates that account-related information (but not the content of any e-mails) could have been viewed, but Microsoft has no indication why that information was viewed or how it may have been used. As a result, you may receive phishing emails or other spam mails. You should be careful when receiving any e-mails from any misleading domain name, any e-mail that requests personal information or payment, or any unsolicited request from an untrusted source (you can read more about phishing attacks at https://docs.microsoft.com/en-us/windows/security/threat-protection/intelligence/phishing).
It is important to note that your email login credentials were not directly impacted by this incident. However, out of caution, you should reset your password for your account.
If you require further assistance, or have any additional questions or concerns, please feel free to reach out to our Incident Response Team at [email protected]. If you are a citizen of European Union, you may also contact Microsoft’s Data Protection Officer at:
EU Data Protection Officer
Microsoft Ireland Operations Ltd
One Microsoft Place,
South County Business Park,
Leopardstown, Dublin 18, Ireland
Microsoft regrets any inconvenience caused by this issue. Please be assured that Microsoft takes data protection very seriously and has engaged its internal security and privacy teams in the investigation and resolution of the issue, as well as additional hardening of systems and processes to prevent such recurrence.