the default on all of my RHEL is to have it disabled, I believe it's the same on Debian based
sysctl -a | grep net.mptcp.enabled net.mptcp.enabled = 0
and golang apps would just gracefully downgrade to non mptcp in that case.
sysctl -a | grep net.mptcp.enabled net.mptcp.enabled = 0
and golang apps would just gracefully downgrade to non mptcp in that case.
"sysctl -a | grep net.mptcp.enabled" gives "net.mptcp.enabled = 1" on Debian 13 (Trixie). That's a non-server desktop install fwiw.
Edit - security advisory is here: (dated Oct 16) https://lists.debian.org/debian-security-announce/2026/msg00...