Security Seminar

Misogyny and domestic abuse are old problems, but tech companies have enabled these harms to grow and proliferate on their platforms in new forms, such as social media harassment, cyberstalking, and deepfake intimate image abuse. This talk will summarise my work to build better systems for survivors of online gender-based...

AI has the potential to transform learning, creativity, and productivity. It represents a profound platform shift in technology – like the internet, or the shift to mobile. As with any transformational shift, AI will be (and already is) used for good and for malicious purposes. This talk will cover some of the practical...

This talk presents the first comprehensive security evaluation of Internet voting systems used in U.S. federal elections. We find that all systems suffer from critical flaws that allow attackers to expose a voter’s private ballot, change votes, or otherwise control an election’s outcome. As a direct result of this work...

End-to-end encryption (E2EE) for messaging has become an industry standard and is widely implemented in many applications. However, applying E2EE to audio calls, particularly group calls, remains a complex challenge. Unlike text messages, audio calls involve capturing audio streams from each participant, which must be...

Abstract not available

Key recovery is the process of regaining access to end-to-end encrypted data after the user has lost their device, but still has their password. Existing E2EE key recovery methods, such as those deployed by Signal and WhatsApp, centralize trust by relying on servers administered by a single provider. In this talk, we share...

End-to-end encryption has become the gold standard for securing communications, bringing strong privacy guarantees to billions of users worldwide. My talk will discuss two potential avenues through which the security protections of end-to-end encryption might be undermined, concerning government circumvention and...

Better algorithms mean less illegal content on social media. To improve these algorithms, users need to report such content, yet they often do not. This talk will explore young people’s attitudes and practices around reporting a specific online harm: illicit drug advertisements. A survey of UK students (13–18) examined...

Dan Sexton is Chief Technology Officer at the Internet Watch Foundation, a not-for-profit whose vision is to create an internet free from child sexual abuse and is a safe place for children and adults to use around the world. Zoom link: https://cam-ac-uk.zoom.us/j/83115049986?pwd=6W5bzFb49HcCbWqz6HR3tRhpVxubTb.1

Dan Sexton is Chief Technology Officer at the Internet Watch Foundation, a not-for-profit whose vision is to create an internet free from child sexual abuse and is a safe place for children and adults to use around the world.