KeyCat opensource password manager

Name: KeyCat opensource password manager
Author: Key.cat

KeyCat is an open source end-to-end encrypted password manager. This is the web-extension companion to automate auto-filling the forms based on the data stored in the password manager The full source code can be found on https://github.com/keydotcat

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Key.cat can manage all your credentials and lets you share them with others. The idea is to make a password manager that can work offline and sync when there's a connection available to the server. Like an auto-sync keepass.

Everything is encrypted end-to-end using NaCL via tweetnacl.js. No metadata leaks. No metadata is stored unencrypted. Single executable for the server. Can import from keepass (v.3 for now). Multiple teams and vaults. Each team and vault can be independently managed and shared with others. Multiple credentials per site. API available to third-party software. More info is in the wiki!

Add-on

By:

Key.cat

Daily users:

Version:

0.0.17 Last updated: 2020-04-08

Version code:

4986983

Creation date:

2018-12-21

Risk:

Permissions:

tabs
storage
clipboardWrite
idle
http://*/*
https://*/*
webRequest
webRequestBlocking

Size:

1.12MB

Email:

ac*****@key.cat

URLs:

Website ,Privacy policy

Full description:

Source:

Firefox Browser Add-ons

Data ingested on:

2025-07-14

Ranking

# 114,467 ▼ 484

Other rankings

#124 in source code keyword 26 ▲ 3 #224 in resource keyword 32 ▼ 1

Extension safety

Risk impact

Risk impact measures the level of extra permissions an extension has access to. A low risk impact extension cannot do much harms, whereas a high risk impact extension can do a lot of damage like stealing your password, bypassing your security settings, and accessing your personal data. High risk impact extensions are not necessarily malicious. However, if they do turn malicious, they can be very harmful.

KeyCat opensource password manager requires some sensitive permissions that could impact your browser and data security. Exercise caution before installing.

Risk impact analysis details

Critical Grants access to browser tabs, which can be used to track user browsing habits and history, presenting a privacy concern.
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Risk likelihood

Risk likelihood measures the probability that a Firefox add-on may turn malicious. This is determined by the publisher and the Firefox add-on reputation on Firefox Browser Add-ons, the amount of time the Firefox add-on has been around, and other signals about the Firefox add-on. Our algorithms are not perfect, and are subject to change as we discover new ways to detect malicious extensions. We recommend that you always exercise caution when installing a Firefox add-on.

KeyCat opensource password manager is probably trust-worthy. Prefer other publishers if available. Exercise caution when installing this add-on.

Risk likelihood analysis details

High This extension has low user count. Unpopular extensions may not be stable or safe.
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