Hiding Secrets in Emojis: Exploiting Unicode Variation Selectors

2025-02-12
Hiding Secrets in Emojis: Exploiting Unicode Variation Selectors

A Hacker News comment sparked a discussion about hiding information using Unicode variation selectors. This article demonstrates that arbitrary data can be encoded into a single emoji by converting data into a sequence of Unicode variation selectors, remaining invisible after rendering. This method can bypass human content filters or be used for text watermarking, enabling covert information transmission and tracking. While this technique has potential for abuse, it also highlights the complexity and potential security challenges of Unicode.