Remote Images Are Causing Problems for Email Filters

Standard phishing attacks and business email compromise (BEC) continue to be a pain point for organizations, but now hackers are upping their game with the use of malicious remote-based images. Instead of embedding images into emails, this tactic allows them to host the images elsewhere and better avoid detection. As a result, most filters must fetch these images over a network to determine if they are safe – a laborious task that cannot be done in real time.


Seeing this trend starting to unfold, Vade Secure researchers wanted to dig a bit deeper and see how real the threat was. In just one month, they detected and analyzed 26.2M remote images, generated 12K Global Network Initiative (GNI) blocking requests and blocked 261M malicious emails leveraging this tactic.


Visit their blog for more information about their findings: https://www.vadesecure.com/en/blog/remote-images-are-pushing-email-filters-to-their-limits