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Firefox Ports Outbound: 50000 - 65535

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  • Last reply by cor-el

SuMo Bot
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Why does Firefox use dynamic ports in the 50K+ range when I use it to browse the web?

I have included screen shots with netstat -AB as well as currports.

Furthermore, if I set a rule in Windows Firewall blocking outbound traffic on ports 50000 - 65535, it breaks DNS with Firefox, even though 53 UDP is open.

I'm not overly concerned with any connection that is localhost / 127.0.0.1.

I've tried prohibiting these ports by modifying user.js - No impact, only works if I implicitly call out the port (example.com:55000)

What do? Why is FF using these ports?

Why does Firefox use dynamic ports in the 50K+ range when I use it to browse the web? I have included screen shots with netstat -AB as well as currports. Furthermore, if I set a rule in Windows Firewall blocking outbound traffic on ports 50000 - 65535, it breaks DNS with Firefox, even though 53 UDP is open. I'm not overly concerned with any connection that is localhost / 127.0.0.1. I've tried prohibiting these ports by modifying user.js - No impact, only works if I implicitly call out the port (example.com:55000) What do? Why is FF using these ports?

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cor-el
cor-el
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See Loopback connection =>

SuMo Bot
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