LAN port scan forbidder

Forbid non-LAN webs to access LAN or localhost. An anti-scan protection
What is LAN port scan forbidder?
LAN port scan forbidder is a Firefox add-on that forbids untrusted websites from scanning localhost or LAN. It provides protection against unauthorized port scans and helps prevent tracking fingerprinting.

Add-on stats

By: GarryW
Users: 43 ▼ -2
Rating: 1.00 (1)
Version: 0.6.2 (Last updated: 2024-03-22)
Creation date: 2021-06-05
Weekly download count: 2
Firefox on Android: Yes
Risk impact: High risk impact
Risk likelihood: Moderate risk likelihood
Manifest version: 2
Permissions:
  • webRequest
  • webRequestBlocking
  • *://*/*
  • ws://*/*
  • wss://*/*
  • ftp://*/*
  • contextMenus
  • storage
  • tabs
Size: 42.76K
URLs: Website

Other platforms

Not available on Chrome
Not available on Edge
Want to check extension ranking and stats more quickly for other Firefox add-ons? Install Chrome-Stats extension to view Chrome-Stats data as you browse the Firefox Browser Add-ons.

Add-on summary

Forbid untrusted web to scan localhost or LAN. Browser addon.

What

Webs can try to fetch 127.0.0.1:xxxx or 192.168.Y.Z:xxxx to scan your open ports in LAN.

Although browsers have cross-domain protections, webs can't read response contents, but can still see the connection succeeds or fails.

There're already reports that some websites using that as tracking fingerprint.

A web for testing: http://samy.pl/webscan/
So

Forbid any website behaviors trying to connect to your LAN or localhost, if user is visiting the website via their domains or public IP addresses. (Read the source code background.js to see the logic)

See more

User reviews

Out of memory crash: https://github.com/garywill/LAN-port-scan-forbidder/issues/4.
by Peter Kehl, 2024-02-24
View all user reviews

Add-on safety

Risk impact

LAN port scan forbidder requires some sensitive permissions that could impact your browser and data security. Exercise caution before installing.

Risk likelihood

LAN port scan forbidder is probably trust-worthy. Prefer other publishers if available. Exercise caution when installing this add-on.

Upgrade to see risk analysis details