Pomoc pśepytaś

Glědajśo se wobšudy pomocy. Njenapominajomy was nigda, telefonowy numer zawołaś, SMS pósłaś abo wósobinske informacije pśeraźiś. Pšosym dajśo suspektnu aktiwitu z pomocu nastajenja „Znjewužywanje k wěsći daś“ k wěsći.

Dalšne informacije

firefox opens a UDP listening port a.k.a backdoor on all network interfaces

  • 3 wótegrona
  • 0 ma toś ten problem
  • 5 naglědow
  • Slědne wótegrono wót Balázs Meskó

more options

On ubuntu oracular 24.10, when firefox is launched, it tries to open a UDP listening port on all network interfaces which is not acceptable on many levels:

/usr/bin/netstat -tunpevaW|grep firefox udp 0 0 0.0.0.0:48654 0.0.0.0:* 1000 881247 178766/firefox

Is this behavior specific to Ubuntu or is it implemented by design? This must be a no go by design: if it needs a UDP port for some reason, it has to open it on the **loopback interface (127.0.0.1)** only.

On ubuntu oracular 24.10, when firefox is launched, it tries to open a UDP listening port on all network interfaces which is not acceptable on many levels: /usr/bin/netstat -tunpevaW|grep firefox udp 0 0 0.0.0.0:48654 0.0.0.0:* 1000 881247 178766/firefox Is this behavior specific to Ubuntu or is it implemented by design? This must be a no go by design: if it needs a UDP port for some reason, it has to open it on the **loopback interface (127.0.0.1)** only.

Wót jean-christophe manciot změnjony

Wšykne wótegrona (3)

more options

Hi Jean-Christophe!

I found this post about this: https://unix.stackexchange.com/a/769645 According to this and others I found, these are most likely used by HTTP/3, which is partially UDP-based. So this isn't Ubuntu-specific at all.

Regards, Balázs

Wót Balázs Meskó změnjony

Wužytny?

more options

Chrome supports HTTP/3 out of the box (which can be checked at https://quic.nginx.org for instance) and does not open UDP or TCP listening ports on all network interfaces:

# /usr/bin/netstat -tunpevaW|grep chrome | grep -P "^(udp|tcp)[[:blank:]]+0[[:blank:]]+0[[:blank:]]+0\.0\.0\.0:"
# 


The HTTP/3 argument does not stand.

Wót Balázs Meskó změnjony

Wužytny?

more options

I can't find any authoritative source, so you can disagree, but it is indeed HTTP/3. If you disable it in about:config no new ports are in netstat's output.

My guess is Chromium's implementation of QUIC is slightly different.

Wót Balázs Meskó změnjony

Wužytny?

Stajśo pšašanje

Musyśo se pla swójogo konta pśizjawiś, aby na pśinoski wótegronił. Pšosym stajśo pšašanje, jolic hyšći njamaśo wužywaŕske konto.