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SECURITY REPORT · EXTENSHI SCAN

KeyCat opensource password manager

Firefox extension·by Key.cat
20
/ 100 SAFETY SCORE
CRITICAL
Severe indicators. Treat as unsafe until the developer addresses these findings.

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

KeyCat opensource password manager's safety score vs every other extension we've scanned
Globally
2%of extensions carry more risk
This extension
Riskier ←→ Safer
Ranked against 409,539 extensions
In Privacy & Security
1%of privacy & security extensions carry more risk
This extension
Riskier ←→ Safer
Ranked against 12,541 privacy & security extensions
Findings
117
median 5Lower is safer
Critical findings
2
median 0Severity = Critical
Permissions
9
median 4Declared in manifest
Active users
1
median 3vs category median

Findings breakdown

Automated security signal · 117 distinct issues across 6 severities
117
distinct issues
detected
Scanners reported 185 raw occurrences; repeats of the same issue at the same location are merged here. The list below shows every occurrence.

Permissions requested

5 risky permissions of 9 total
5 high-risk permissions require attention
This extension requests 9 permissions in total. 5 of them grant broad capabilities that are worth a careful look.
High
View open tabs

Can see URLs and titles of all open tabs

High
Access all HTTP sites

Can read and modify content on all non-encrypted websites

High
Access all HTTPS sites

Can read and modify content on all encrypted websites

High
Observe web requests

Can monitor all network requests made by the browser

High
Block and modify web requests

Can intercept, block, or modify any network request before it completes

Medium
Store local data

Can save data locally in the browser for persistence

Medium
Write to clipboard

Can place content onto your clipboard

Low
Detect idle state

Can detect when your machine is idle, active, or locked

Info
file:///*

No additional information available.

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Scan performed by extenshi.io · Aug 14, 2026
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