Malicious VS Code Extensions Delivering Trojan Payloads via Impersonation and Encrypted Loaders
Security researchers reported malicious Visual Studio Code extensions being used as a software supply-chain vector to compromise developer workstations. One campaign impersonated a viral AI coding assistant (“ClawdBot”) via a fake extension (“ClawdBot Agent”) that appeared legitimate and even functioned as an AI assistant by integrating real APIs (e.g., OpenAI/Anthropic/Google), while silently dropping malware on Windows at VS Code startup. The observed payload delivery used camouflage filenames such as Lightshot.exe (and references to Lightshot.dll) and an Electron-style bundle name Code.exe, indicating an effort to blend into common developer tooling and evolve the dropper over time.
A separate finding described an Open VSX extension masquerading as a popular Angular Language Service for VS Code, which bundled legitimate dependencies (e.g., @angular/language-service and typescript) alongside a malicious loader that activates when users open HTML or TypeScript files (onLanguage:html, onLanguage:typescript). The loader decrypts an embedded payload using AES-256-CBC (Node.js crypto), with a hardcoded IV and a large hex-encoded ciphertext, then delays and executes the decrypted code—behavior consistent with staged malware delivery and potential worm-like propagation through widely installed editor extensions.
Timeline
Jan 29, 2026
Microsoft removes malicious 'ClawdBot Agent' from VS Code marketplace
After the extension was reported, Microsoft quickly removed 'ClawdBot Agent' from the marketplace. At the time of takedown, the extension had recorded 21 installs.
Jan 28, 2026
Malicious Angular-themed extension reaches activation threshold
The Open VSX extension activated its malicious logic after reaching 5,066 downloads. Once triggered, it used encrypted JavaScript, Solana-based etherhiding command-and-control, and later-stage payload delivery to deploy a stealer targeting developer tokens, browser data, and crypto wallets.
Jan 27, 2026
Researchers discover fake 'ClawdBot Agent' VS Code extension
Aikido Security researcher Charlie Eriksen discovered a malicious Visual Studio Code extension named 'ClawdBot Agent' on January 27, 2026. The extension impersonated the ClawdBot AI coding assistant while functioning as a trojan that dropped malware on Windows systems when VS Code launched.
Jan 14, 2026
Malicious Angular-themed VS Code extension appears on Open VSX
A malicious Visual Studio Code extension impersonating the Angular Language Service was hosted on Open VSX and remained available for about two weeks. It bundled legitimate Angular and TypeScript components while hiding an encrypted multi-stage malware loader.
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