unexpected behavior: q binds to an unexpected interface and bypasses routing table to send traffic over such interface

[sumple]

qBittorrent & operating system versions

qbittorrent-5.0.0-1-x86_64.pkg.tar.zst
Operating system: Arch
Qt: qt6-base-6.8.0-1-x86_64.pkg.tar.zst
libtorrent-rasterbar: libtorrent-rasterbar-1:2.0.10-3-x86_64.pkg.tar.zst

What is the problem?

My system has an eth0 interface which has default route to internet.
And another vpn interface which has only a few dedicated routes for internal subnets(rfc1918).

Normally application should source from eth0 intf and send data packet over eth0 intf only.
Today I noticed that Q bound to vpn intf and sent data packet over vpn intf.
This was verified by tcpdump.
I'm caught by great surprise and just want to report it in.

Steps to reproduce

No response

Additional context

No response

Log(s) & preferences file(s)

No response