Top Risks

• Critical CVE-2021-23358 in bundled underscore@1.8.3 (arbitrary code execution); unfixed version in production.
• No content_security_policy on MV3 extension with <all_urls> and innerHTML sinks amplifies XSS risk.
• 5 dom_sink_innerhtml_userctrl findings across polyfill and content script files with no CSP mitigation.
• Privacy policy is generic Google policy (scope_extension=false); does not disclose what this extension collects.
• 3M+ installs means high blast radius if vulnerabilities are exploited or extension is compromised.

Evidence

• cve_critical_underscore crx underscore@1.8.3 has CVE-2021-23358 (critical, arbitrary code execution); fixed in 1.12.1.
• cve_high_underscore crx underscore@1.8.3 has CVE-2026-27601 (high, DoS via unlimited recursion); fixed in 1.13.8.
• no_csp_with_innerhtml crx No CSP declared; 5 innerHTML-from-variable sinks in polyfills and content scripts.
• generic_privacy_policy store Privacy policy is google.com/intl/en/policies/privacy/; scope_extension=false, no extension-specific disclosure.
• broad_host_access manifest <all_urls> host permission with scripting enables read/write on all sites.
• google_dev_email store Dev email tag-assistant-publisher@google.com; confirmed_owner=true, not impersonation.
• monetization_hit_gtm crx www.googletagmanager.com in monetization_hits; contextually expected for Tag Assistant.
• high_install_blast_radius store 3,000,000 installs; vulnerability exploitation would have wide reach.

CVE Exposures (2)

Permissions Breakdown

• scripting medium Can inject scripts into pages; paired with <all_urls> elevates risk.
• sidePanel low UI surface only; no data access.
• storage low Local extension storage; no cross-site risk.
• tabs medium Can read tab URLs and metadata; moderate privacy surface.
• webNavigation medium Observes navigation events across all pages; privacy surface.
• <all_urls> high Broad host access across all sites; enables reading/modifying any page content.

Pillar Scores

Scoring History

Bookkeeping