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Office 365 Email baseStriker Vulnerability

A vulnerability named baseStriker has been discovered in Office 365 which allows threat actors to deliver malicious emails.
Report a cyber attack: call 0300 303 5222 or email [email protected]

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Summary

A vulnerability named baseStriker has been discovered in Office 365 which allows threat actors to deliver malicious emails.

Threat details

Using the base tag in HyperText Markup Language (HTML), it is possible to create a link in an email without including the full location that the link leads to. At the time of publication this method of linking is not analysed properly by Microsoft's security services, and so emails containing such links to malicious locations may not be blocked.

Attackers are currently exploiting this vulnerability in phishing attacks, but it is also possible to deliver links to malware and other malicious content.


Remediation steps

Type Step
Ensure that a robust program of education and awareness training is delivered to users to ensure they don’t follow links within unsolicited emails.

Last edited: 17 February 2020 12:51 pm