Researchers Uncover 73 Fake VS Code Extensions Delivering GlassWorm v2 Malware

Summary

Cybersecurity researchers identified 73 cloned VS Code extensions on the Open VSX repository linked to the GlassWorm information-stealing campaign, with 6 confirmed malicious and 67 acting as sleeper packages to build trust before deployment. The threat actors use typosquatting, visual spoofing, and subsequent updates to distribute GlassWorm v2, which targets multiple IDEs (VS Code, Cursor, Windsurf, VSCodium) to steal credentials, install RATs, and deploy rogue browser extensions. Since December 21, 2025, over 320 artifacts have been identified in this evolving campaign that uses Zig-based droppers and obfuscated JavaScript loaders to evade detection.

Full text

Researchers Uncover 73 Fake VS Code Extensions Delivering GlassWorm v2 Malware Ravie LakshmananApr 27, 2026Malware / Software Supply Chain Cybersecurity researchers have flagged dozens of Microsoft Visual Studio Code (VS Code) extensions on the Open VSX repository that are linked to a persistent information-stealing campaign dubbed GlassWorm. The cluster of 73 extensions has been identified as cloned versions of their legitimate counterparts. Of these, six have been confirmed to be malicious, with the remaining acting as seemingly harmless sleeper packages to get users to download them and build trust, before their true intent is manifested through a subsequent update. All the extensions were published at the start of the month, per application security company Socket, which is tracking the latest iteration under the moniker GlassWorm v2. In total, more than 320 artifacts have been identified since December 21, 2025. The list of extensions identified as malicious is below - outsidestormcommand.monochromator-theme keyacrosslaud.auto-loop-for-antigravity krundoven.ironplc-fast-hub boulderzitunnel.vscode-buddies cubedivervolt.html-code-validate winnerdomain17.version-lens-tool The cloned sleepers, besides typosquatting the names of the original packages (CEINTL.vscode-language-pack-tr vs. Emotionkyoseparate.turkish-language-pack), use the same icon and description as their corresponding legitimate versions in an attempt to fool unsuspecting developers and trick them into installing the extensions. This "visual trust" acts as an effective social engineering tactic to boost install counts organically before it's poisoned to serve malware to the downstream users. The disclosure comes as the threat actors behind the campaign are actively evolving their modus operandi, pivoting to sleeper packages and transitive dependencies to evade detection, while simultaneously using Zig-based droppers to deploy a secondary VSIX extension hosted on GitHub that can infect all integrated development environments (IDEs) on a developer's machine. The extensions identified by Socket act as an innocuous loader for the actual payload, which is a VSIX extension that's retrieved from GitHub and installed into every IDE identified in the system, including VS Code, Cursor, Windsurf, and VSCodium, using the "--install-extension" command. Irrespective of the method used, the end goal is the same: run malware that avoids Russian systems, steal sensitive data, install a remote access trojan (RAT), and stealthily deploy a rogue Chromium-based extension to siphon credentials, bookmarks, and other information. "This approach achieves the same outcome as the binary-based variant, but keeps the delivery logic in obfuscated JavaScript," the company said. "The extension acts as a loader, while the payload is retrieved and executed after activation." Found this article interesting? Follow us on Google News, Twitter and LinkedIn to read more exclusive content we post. SHARE     Tweet Share Share Share SHARE  cybersecurity, Developer Tools, Information Stealer, Malware, Open Source, Remote Access Trojan, social engineering, Software Supply Chain, Threat Intelligence, Visual Studio Code Trending News Harvester Deploys Linux GoGra Backdoor in South Asia Using Microsoft Graph API Malicious KICS Docker Images and VS Code Extensions Hit Checkmarx Supply Chain Apple Fixes iOS Flaw That Let FBI Recover Deleted Signal Messages Vercel Finds More Compromised Accounts in Context.ai-Linked Breach ThreatsDay Bulletin: $290M DeFi Hack, macOS LotL Abuse, ProxySmart SIM Farms +25 New Stories Bitwarden CLI Compromised in Ongoing Checkmarx Supply Chain Campaign LMDeploy CVE-2026-33626 Flaw Exploited Within 13 Hours of Disclosure FIRESTARTER Backdoor Hit Federal Cisco Firepower Device, Survives Security Patches Researchers Uncover Pre-Stuxnet ‘fast16’ Malware Targeting Engineering Software ⚡ Weekly Recap: Fast16 Malware, XChat Launch, Federal Backdoor, AI Employee Tracking and More Checkmarx Confirms GitHub Repository Data Posted on Dark Web After March 23 Attack Microsoft Confirms Active Exploitation of Windows Shell CVE-2026-32202 Chinese Silk Typhoon Hacker Extradited to U.S. Over COVID Research Cyberattacks Microsoft Patches Entra ID Role Flaw That Enabled Service Principal Takeover Researchers Discover Critical GitHub CVE-2026-3854 RCE Flaw Exploitable via Single Git Push Critical cPanel Authentication Vulnerability Identified — Update Your Server Immediately Popular Resources Discover Key AI Security Gaps CISOs Face in 2026 Fix Rising Application Security Risks Driven by AI Development Automate Alert Triage and Investigations Across Every Threat How to Identify Risky Browser Extensions in Your Organization

Indicators of Compromise

• malware — GlassWorm v2
• malware — GoGra
• malware — FIRESTARTER

Entities