Open VSX Supply Chain Attack Used Compromised Dev Account to Spread GlassWorm

According to Socket Security researcher Kirill Boychenko, Open VSX was hit by a supply‑chain attack in which a legitimate developer’s resources were compromised to push malicious updates to downstream users. On 30 January 2026, four established Open VSX extensions published by the oorzc author received malicious versions that embed the GlassWorm malware loader, with the extensions having previously gathered more than 22,000 downloads.

The incident involved the compromise of the developer’s publishing credentials, with the Open VSX security team assessing that a leaked token or other unauthorized access was used; the malicious versions have since been removed.

The poisoned extensions—FTP/SFTP/SSH Sync Tool (oorzc[.]ssh-tools, 0.5.1), I18n Tools (oorzc.i18n-tools-plus, 1.6.8), vscode mindmap (oorzc[.]mind-map, 1.0.61), and scss to css (oorzc[.]scss-to-css-compile, 1.3.4)—were designed to deliver a loader that decrypts and runs embedded code at runtime and to fetch C2 endpoints via EtherHiding.

The payload also targets crypto wallets and browser data, including iCloud Keychain, Firefox/Chromium data, and developer credentials, which could enable cloud‑account compromise and lateral movement.