The influencer economy blurs personal sharing and commercial activity, creating legal gaps over liability for deceptive claims, fake reviews, and unfair competition. This article analyzes the legal roles of influencers, brands, and platforms, comparing Vietnam's framework with those of the United States, the European Union, and the United Kingdom. It shows that, although Vietnam's 2025–2026 legislative updates have begun to define influencer responsibilities, these rules remain institutionally disconnected from the Competition Law 2018. As a consequence, the mechanisms of joint liability, the standards of disclosure, and the level of sanctions fail to match the scale of potential digital harm. To address this, the article proposes some solutions that would integrate these instruments into a unified liability framework. These measures aim to hold the key actors in the digital market accountable for dishonest commercial promotion. Ultimately, closing these legislative gaps would better safeguard online consumers and foster fair competition in the marketplace.