SECURITY REPORT · EXTENSHI SCAN
Check XSS
Firefox extension·by Gray Sky
0
/ 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 6 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
64%of extensions carry more risk
Riskier ←→ Safer
Ranked against 369,936 extensions
In Privacy & Security
49%of privacy & security extensions carry more risk
Riskier ←→ Safer
Ranked against 11,537 privacy & security extensions
Findings
6
median 5Lower is safer
Critical findings
0
median 0Severity = Critical
Permissions
4
median 4Declared in manifest
Active users
278
median 3vs category median
Findings breakdown
Automated security signal · 6 distinct issues across 6 severities
6
distinct issues
detected
detected
Critical00%
High00%
Needs Review00%
Medium583%
Low117%
Info00%
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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