Osprey – Browser extension that protects you from malicious websites
26 comments
·April 13, 2025mfrisbie
Foulest
The same thing happens with Google's SafeBrowsing, Microsoft's SmartScreen, Bitdefender TrafficLight, or Emsisoft Browser Protection. Osprey essentially combines multiple already existing browser protection extensions into one.
_Algernon_
Not sure what this provides that a malicious site list for uBlock Origin provides in a better, more privacy preserving way.
Foulest
uBlock Origin's filters aren't up-to-date. You can go to PhishTank and try all the recently added websites on a VM. uBlock won't block any of them.
SamuelAdams
How is this different from setting your DNS to a malware-blocking domain provider? For example Cloudflare’s malware dns is 1.1.1.2, Quad9 blocks malware by default with 9.9.9.9.
RamRodification
Two obvious differences to me:
Since it's a browser extension, it does not offer any protection outside the browser. If you use a DNS service with malware blocking it will, in theory, "protect" any DNS lookup your system performs. Including lookups that originate from software other than your web browser.
It also differs by using several different services to check all URLs (there's a list in the readme). If you set your DNS to Cloudflare and/or Quad9 you will only get protection from one of those.
I can think of pros and cons with both of these aspects.
wopurs
I don't like the fact that it's sending all websites a user visits to a bunch of companies, specially companies that are not EU based.
Foulest
It uses the same exact framework as Google SafeBrowsing and Microsoft SmartScreen.
xnx
1) Why is this better than using the built in Chrome or Microsoft protections?
2) How do I know this isn't logging every URL I visit back to Osprey?
gorhill
When you enable "Developer mode" in the "Extensions" page of your browser, you can open the developer tools for the extension by clicking the "service worker" link, and from there select the "Network" tab, you will be able all the network requests made by the extension from within its service worker.
gabrielsroka
I just started using uBO Lite on Chrome. Brave is my daily driver and I just can't surf the web without an ad blocker anymore. I resisted it for years.
Thank you for all you do!
Foulest
Thanks gorhill. Yes, this is true! Osprey only sends its stripped-down URLs to the services you turn on. Nothing more. It's as anonymous as it can be without using a VPN, afaik.
Foulest
1) Osprey is just more protections built into one. It combines seven pre-existing safe browsing extensions you can already download into one lighter and better extension. All these extensions do is send the URL you visit to an API. That's what SmartScreen and Google SafeBrowsing do. 2) Read gorhill's comment. Checking network activity is easy, and checking every extension is always good.
jeroenhd
Chrome and Edge contain just one single source of malicious website reports.
This addon uses multiple data sources.
As for logging: this submits URLs to various services. This is unlike Google Safe Browsing, which has a "periodically sync an offline database" setting (but will also send URLs to Google by default).
andy99
On 2, it appears to be open source so you could look and see if/what it logs.
tgv
I seems to send all urls you visit to Microsoft, Symantec, Emisoft, Webshield, Norton, Gdata Security, and/or BitDefender, depending on your settings. And of course, those URLs can be changed on the next update.
Foulest
This is true, and they do. I'm replacing Comodo's Valkyrie API with Symantec's Browser Protection API for performance reasons. But, no data is logged, and only the minimum amount of data is sent to each provider.
true_blue
ublock Origin already has a feature called "strict blocking" which does the same thing. In fact, the placeholder page that this extension takes you to looks almost exactly the same as the one that ublock origin uses.
RamRodification
> does the same thing
Does that feature really send each URL you attempt to browse to a bunch of third-party services to be verified before it lets you browse them?
Edit: Made some not-very-thorough research and it seems like "strict blocking" in uBlock Origin does not do the same thing. It does local lookups against regularly updated filter lists. Like all of uBlock Origin's blocking, I guess.
Foulest
Osprey is entirely asynchronous. It doesn't hold pages at all. If you visit an unsafe website, you might see it for 50-250ms before the connection is stopped.
RamRodification
Good to know!
Foulest
I promise the warning page was made from scratch!
alwa
I’m curious how much those 7 lists overlap. Surely there must be a lot of unambiguous cases, but I wonder how much is on the margins.
throwaway290
Does it protect you from malicious extensions including possible future versions of itself? :)
So this extension is feeding a stream of your browsing activity to a bunch of third party services? No thanks.