OpenSnitch
Open-source interactive application firewall for Linux that prompts on outbound connections.
HN commenters recommend it as a Linux counterpart to Little Snitch that alerts on every new outbound connection123, often layered with sandboxing and valued for being free.45 Complaints are rare; one commenter saw it attribute a connection to the wrong browser6, and another called this kind of setup tedious.7
Why people recommend it
Connection visibility · 3
Alerts on new connections so users see what their machine is contacting.
“I use OpenSnitch, which alerts me about all new connections.”
“Fist program to be installed.”
Show 1 more
“Little Snitch on macOS and Open Snitch on Linux have helped me a lot here”
Layered security · 2
Used alongside bubblewrap sandboxes or Qubes VMs for defense in depth.
“On top of this, I use opensnitch.”
“I use OpenSnitch, which alerts me about all new connections.”
Free · 1
Seen as a free tool that already does what paid alternatives charge for.
“I'm certainly not going to spend $60 for something that has been doing the job for free.”
Caveats and dissent
Process attribution · 1
One user saw a request attributed to Chromium that may have come from Firefox.
“opensnitch caught the request but shows chromium instead of firefox”
Setup effort · 1
Combining it with sandboxing was described as tedious to set up.
“On top of this, I use opensnitch.”
Often compared with
Who recommends it in their own words
Threads where it came up
- Little Snitch Shows Who Your Mac Talks To 1 mention
- Telegram Desktop vulnerability allowed any user's file to be stolen 1 mention
- How can perplexity.com persist on the browser without extension 1 mention
- LittleSnitch for Linux 1 mention
- The Cloudflare outage might be a good thing 1 mention
- Ask HN: Securing Pip and NPM package use? 1 mention
Data: opensnitch.json. Quotes are verbatim; the verdict and theme labels are written by a model from these comments, and every clause links to its sources.
All comments 6
“Fist program to be installed.”
“On top of this, I use opensnitch.”
“opensnitch caught the request but shows chromium instead of firefox”
“I'm certainly not going to spend $60 for something that has been doing the job for free.”
“Little Snitch on macOS and Open Snitch on Linux have helped me a lot here”
“I use OpenSnitch, which alerts me about all new connections.”