PhishGAN: Data Augmentation and Identification of Homoglyph Attacks

Homoglyph attacks are a common technique used by hackers to conduct phishing. Domain names or links that are visually similar to actual ones are created via punycode to obfuscate the attack, making the victim more susceptible to phishing. For example, victims may mistake “linkedin.com” for “linkedin.com” and in the process, divulge personal details to the fake website. Current State of The Art (SOTA) typically make use of string comparison algorithms (e.g. Levenshtein Distance), which are computationally heavy. One reason for this is the lack of publicly available datasets, hindering the training of more advanced Machine Learning (ML) models. Furthermore, no one font is able to render all types of punycode correctly, posing a significant challenge to the creation of a dataset that is unbiased toward any particular font. This coupled with the vast number of internet domains pose a challenge in creating a dataset that can capture all possible variations. Here, we show how a conditional Generative Adversarial Network (GAN), PhishGAN, can be used to generate images of hieroglyphs, conditioned on non-homoglyph input text images. Practical changes to current SOTA were required to facilitate the generation of more varied homoglyph text-based images. We also demonstrate a workflow of how PhishGAN together with a Homoglyph Identifier (HI) model can be used to identify the domain the homoglyph was trying to imitate. Furthermore, we demonstrate how PhishGAN's ability to generate datasets on the fly, facilitating the quick adaptation of cybersecurity systems to detect new threats as they emerge.