ClaudeBleed Vulnerability Enables Hijacking of Claude Chrome Extension to Exfiltrate Google Drive and Gmail Data
What Happened — Researchers identified a flaw in the Claude‑for‑Chrome extension that lets threat actors bypass built‑in guardrails and siphon private Google Drive files and Gmail messages. The exploit works by injecting malicious scripts into the extension’s runtime, turning the AI assistant into a data‑stealing proxy.
Why It Matters for TPRM —
- Third‑party SaaS tools embedded in browsers can become covert data exfiltration channels.
- Sensitive corporate communications and documents may be exposed without any visible breach indicator.
- Vendor risk assessments must now include extension‑level security reviews, not just API or service‑level controls.
Who Is Affected — Enterprises that allow employees to install the Claude Chrome extension (technology, finance, professional services, consulting, and any organization handling confidential documents).
Recommended Actions —
- Immediately inventory and, if not essential, disable the Claude Chrome extension across the organization.
- Request a formal remediation timeline from Anthropic (the extension’s publisher) and verify the release of a patched version.
- Conduct a focused review of Google Workspace logs for anomalous access patterns during the exposure window.
- Update third‑party risk questionnaires to include extension‑security controls and continuous monitoring.
Technical Notes — The vulnerability is a client‑side code execution flaw (CVE‑pending) that allows malicious JavaScript to run with the extension’s privileges, enabling direct calls to Google Drive and Gmail APIs. No public CVE number has been assigned yet. Data types at risk include email content, attachments, and any files stored in Google Drive. Source: HackRead