Open VSX extensions hijacked: GlassWorm malware spreads via dependency abuse

Threat actors are exploiting the Open VSX extension registry in a new phase of the GlassWorm supply-chain campaign. At least 72 malicious extensions have been identified since January 31, 2026. The attack works by publishing clean-looking extensions that later update to add dependencies on hidden payload packages containing the GlassWorm loader. VS Code's automatic dependency installation then silently delivers the malware. Extensions impersonate popular developer tools like ESLint, Prettier, and AI coding assistants including Claude Code and Codex. Socket researchers recommend auditing extension dependencies, monitoring updates, and restricting installs to trusted publishers. Open VSX has removed most flagged extensions, but some remain live.