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SECURITY REPORT · EXTENSHI SCAN

Check XSS

Firefox extension·by Gray Sky
61
/ 100 SAFETY SCORE
RISKY
Several elevated signals. Read the findings before sharing this with your team.

Likely abandonedsafety score reduced by 30 points

  • No update in over 7 years
Why this matters

An unmaintained extension keeps whatever flaws it shipped with, and a listing with users but no owner is an attractive target to buy and repurpose.

Automated analysis of publicly available code — not a professional security audit. It may produce false positives and does not prove an extension is unsafe or safe. Treat it as one signal among many. Disclaimer · Report an issue

How it ranks

Check XSS's safety score vs every other extension we've scanned
Globally
65%of extensions carry more risk
This extension
Riskier ←→ Safer
Ranked against 409,596 extensions
In Privacy & Security
51%of privacy & security extensions carry more risk
This extension
Riskier ←→ Safer
Ranked against 12,550 privacy & security extensions
Findings
6
median 5Lower is safer
Critical findings
0
median 0Severity = Critical
Permissions
4
median 4Declared in manifest
Active users
282
median 3vs category median

Findings breakdown

Automated security signal · 6 distinct issues across 6 severities
6
distinct issues
detected

Permissions requested

4 permissions declared
No risky permissions
4 permissions requested — none are flagged as risky.
Medium
Custom menus

Can add custom items to the browser context menu

Medium
Access current tab

Can temporarily access the content of the active tab when you click the extension

Medium
Read clipboard

Can read text and data currently on your clipboard

Medium
Write to clipboard

Can place content onto your clipboard

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Scan performed by extenshi.io · Aug 1, 2026
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