Understanding why phishing attacks are so effective and how to mitigate them

Elie Bursztein, Security & Anti-abuse Research Lead, Daniela Oliveira, Professor at the University of Florida




Phishing attacks continue to be one of the common forms of account compromise threats. Every day, Gmail blocks more than 100 million phishing emails and Google Safe Browsing helps protect more than 4 billion devices against dangerous sites. 


As part of our ongoing efforts to further protect users from phishing, we’re partnering with  Daniela Oliveira from the University of Florida during a talk at Black Hat 2019 to explore the reasons why social engineering attacks remain effective phishing tactics, even though they have been around for decades.



Overall, the research finds there are a few key factors that make phishing an effective attack vector:
  • Phishing is constantly evolving: 68% of the phishing emails blocked by Gmail today are new variations that were never seen before. This fast pace adversarial evolution requires humans and machines to adapt very quickly to prevent them.
  • Phishing is targeted:  Many of the campaigns targeting Gmail end-users and enterprise consumers only target a few dozen individuals. Enterprise users being 4.8x more targeted than end-users.
  • Phishers are persuasion experts: As highlighted by Daniela’s research with Natalie Ebner et al. at the University of Florida, phishers have mastered the use of persuasion techniques, emotional salience and  gain or loss framing to trick users into reacting to phishing emails.
  • 45% of users don’t understand what phishing is: After surveying Internet users, we found that 45% of them do not  understand what phishing is or the risk associated with it. This lack of awareness increases the risk of being phished and potentially hinders the adoption of 2-step verification. 


Protecting users against phishing requires a layered defense approach that includes:
  • Educating users about phishing so they understand what it is, how to detect it and how to protect themselves.
  • Leveraging the recent advances in AI to build robust phishing detections that can keep pace with fast  evolving phishing campaigns.
  • Displaying actionable phishing warnings that are easy to understand by users so they know how to react when they see them.
  • Using strong two factor authentication makes it more difficult  for phishers to compromise accounts. Two-factor technologies, as visible in the graph above, can be effective against the various forms of phishing, which highlights the importance of driving awareness and adoption among users.  
While technologies to help mitigate phishing exist, such as FIDO standard security keys, there is still work to be done to help users increase awareness understand how to protect themselves against phishing.