SECURITY REPORT · EXTENSHI SCAN
uMatrix
Firefox extension·by Raymond Hill
0
/ 100 SAFETY SCORE
DANGEROUS
Meaningful risk surface. Avoid on managed devices without review.
Likely abandonedsafety score reduced by 30 points
- No update in over 5 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
uMatrix's safety score vs every other extension we've scanned
Globally
6%of extensions carry more risk
Riskier ←→ Safer
Ranked against 369,936 extensions
In Privacy & Security
4%of privacy & security extensions carry more risk
Riskier ←→ Safer
Ranked against 11,537 privacy & security extensions
Findings
34
median 5Lower is safer
Critical findings
1
median 0Severity = Critical
Permissions
11
median 4Declared in manifest
Active users
14250
median 3vs category median
Findings breakdown
Automated security signal · 34 distinct issues across 6 severities
34
distinct issues
detected
detected
Critical13%
High515%
Needs Review00%
Medium1956%
Low926%
Info00%
Permissions requested
9 risky permissions of 11 total
1 critical permission require attention
This extension requests 11 permissions in total. 9 of them grant broad capabilities that are worth a careful look.
Critical
Access to all websites
Can read and modify content on every website you visit
High
Delete browsing data
Can remove browsing history, cookies, cache, and other browsing data
High
Access browser cookies
Can read and modify cookies, potentially accessing login sessions
High
Control privacy settings
Can modify browser privacy settings like Do Not Track and safe browsing
High
View open tabs
Can see URLs and titles of all open tabs
High
Observe web requests
Can monitor all network requests made by the browser
Medium
Store local data
Can save data locally in the browser for persistence
Medium
Monitor navigation
Can observe and track tab navigation events and URL changes
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Scan performed by extenshi.io · Aug 24, 2026
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