# How to Audit Chrome Extensions for Security Risk

> Browser extensions run with broad access to everything you do online, making them a real and often-ignored attack surface. How to audit Chrome extensions for security risk across your organisation.

Source: https://playciso.com/blog/chrome-extension-security-audit-guide · Published: 2026-09-26 · Publisher: PlayCISO (https://playciso.com)

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Browser extensions sit in a blind spot: they run inside your authenticated sessions, can often read and change every page you visit, and update themselves silently — yet most organisations have no inventory of what employees have installed. That combination of broad access and silent change makes extensions a real attack surface, and a periodic audit is how you keep it in check. ## The risk model An extension with "read and change all your data on all websites" permission can see and manipulate anything in your browser, including data inside apps you are logged into. Because extensions auto-update, a safe extension can turn malicious after an update or after its developer sells it — a repeatedly-seen supply-chain pattern. Broad access + silent change = the core risk. ## The audit process - Inventory. Enumerate installed extensions across the fleet via browser management or endpoint tooling — you cannot manage what you cannot see. - Review permissions vs purpose. For each extension, compare requested permissions to what its function actually needs. A calculator that wants to read every website is a red flag. - Check reputation and updates. Publisher reputation, user base, and update/ownership history — extensions that changed hands deserve scrutiny. - Flag and decide. Excessive permissions, poor reputation or unclear ownership → block or review. ## Enforce a policy at scale Use browser enterprise management (Chrome policies) to allowlist approved extensions, block the rest, prevent silent installs, and control permissions — then re-audit periodically so newly-risky extensions are caught after updates. Scan a specific extension with the free [Extension Scanner →](/tools/extension-scanner). ## Frequently asked questions **Why are extensions risky?** Broad access to your sessions plus silent auto-updates — a safe extension can turn malicious after an update or sale. **How do I audit them?** Inventory the fleet, review permissions vs purpose, check reputation/updates, flag and decide. **Which permissions concern?** "Read/change all data on all sites", history, cookies, managing other extensions — when they exceed purpose. **Control at scale?** Browser enterprise policies: allowlist, block, prevent silent installs, re-audit.