untrusted comment: verify with openbsd-75-base.pub
RWRGj1pRpprAfhXtxWkPg5QGkFKLuuHUoYgjG+1iMb1Jnbm3/ZNDxlGNnvyI47Ox/CLkrkMBaX4ZjHsR3L1J9WuPHGqhqWDciwk=

OpenBSD 7.5 errata 023, April 9, 2025:

sshd(8) fix the DisableForwarding directive, which was failing to
disable X11 forwarding and agent forwarding as documented.

Apply by doing:
   signify -Vep /etc/signify/openbsd-75-base.pub -x 023_ssh.patch.sig \
       -m - | (cd /usr/src && patch -p0)

And then rebuild and install OpenSSH:
   cd /usr/src/usr.bin/ssh
   make obj
   make
   make install

Index: usr.bin/ssh/session.c
===================================================================
RCS file: /cvs/src/usr.bin/ssh/session.c,v
diff -u -p -r1.337 session.c
--- usr.bin/ssh/session.c       1 Feb 2024 02:37:33 -0000       1.337
+++ usr.bin/ssh/session.c       3 Apr 2025 09:52:17 -0000
@@ -1871,7 +1871,8 @@ session_auth_agent_req(struct ssh *ssh,
       if ((r = sshpkt_get_end(ssh)) != 0)
               sshpkt_fatal(ssh, r, "%s: parse packet", __func__);
       if (!auth_opts->permit_agent_forwarding_flag ||
-           !options.allow_agent_forwarding) {
+           !options.allow_agent_forwarding ||
+           options.disable_forwarding) {
               debug_f("agent forwarding disabled");
               return 0;
       }
@@ -2254,7 +2255,7 @@ session_setup_x11fwd(struct ssh *ssh, Se
               ssh_packet_send_debug(ssh, "X11 forwarding disabled by key options.");
               return 0;
       }
-       if (!options.x11_forwarding) {
+       if (!options.x11_forwarding || options.disable_forwarding) {
               debug("X11 forwarding disabled in server configuration file.");
               return 0;
       }