Top Risks

• Critical CVE-2021-23358 in bundled underscore@1.8.3 enables arbitrary code execution; unfixed for 32 months.
• Privacy policy is Google's generic account policy — not scoped to this extension, admits data collection and 3rd-party sharing.
• Extension last updated October 2023 (32 months stale); no active maintenance despite 400K installs.
• Dynamic script creation and new Function() constructor present with no CSP; code execution surface amplified by CVEs.
• 10 external JS hosts resolved (GitHub, CSS theme sites) — exceeds expected surface for a focused AI companion.

Evidence

• critical_cve_underscore crx underscore@1.8.3 bundles CVE-2021-23358 (critical, ACE); fixed in 1.12.1 — still at vulnerable version.
• high_cve_underscore crx underscore@1.8.3 also affected by CVE-2026-27601 (high, DoS via recursion); fixed in 1.13.8.
• privacy_policy_generic_google store Privacy URL is myaccount.google.com/privacypolicy — Google's own policy, not Perplexity's; scope_extension=false, admits 3rd-party sharing.
• stale_extension store Last updated Oct 2023; 32 months since update with 400K installs and active CVEs.
• no_csp crx content_security_policy is null; MV3 provides some default but no explicit CSP hardening while CVEs present.
• dynamic_script_and_function_constructor crx script_src_dynamic + function_constructor in runtime.js/8558.js — code execution patterns without CSP mitigation.
• 10_external_js_hosts crx js_external_hosts includes 10 domains (GitHub, CSS theme sites); >3 distinct registrable domains.
• verified_publisher_confirmed_owner store verified_publisher=true, brand_mention.confirmed_owner=true, developer domain perplexity.ai resolves. Limits reputation risk.

CVE Exposures (2)

Permissions Breakdown

• activeTab medium Grants access to current tab on user action; limited scope but enables page content reads.
• scripting medium Can inject JS/CSS into pages; combined with activeTab enables content extraction.
• https://www.perplexity.ai/ low Scoped host permission to developer's own domain only.
• wss://www.perplexity.ai/ low WebSocket to dev-owned domain; expected for AI query streaming.

Pillar Scores

Bookkeeping