cockpit/tools/libssh.supp

# https://red.libssh.org/issues/258
{
   ssh_userauth_kbdinit_leak
   Memcheck:Leak
   match-leak-kinds: definite
   ...
   fun:ssh_userauth_kbdint
   fun:do_interactive_auth
   fun:cockpit_ssh_authenticate
   ...
}