do_rc_files(Session *s, const char *shell)
{
	FILE *f = NULL;
	char cmd[1024];
	int do_xauth;
	struct stat st;

	do_xauth =
	    s->display != NULL && s->auth_proto != NULL && s->auth_data != NULL;

	/* ignore _PATH_SSH_USER_RC for subsystems and admin forced commands */
	if (!s->is_subsystem && options.adm_forced_command == NULL &&
	    !no_user_rc && options.permit_user_rc &&
	    stat(_PATH_SSH_USER_RC, &st) >= 0) {
		snprintf(cmd, sizeof cmd, "%s -c '%s %s'",
		    shell, _PATH_BSHELL, _PATH_SSH_USER_RC);
		if (debug_flag)
			fprintf(stderr, "Running %s\n", cmd);
		f = popen(cmd, "w");
		if (f) {
			if (do_xauth)
				fprintf(f, "%s %s\n", s->auth_proto,
				    s->auth_data);
			pclose(f);
		} else
			fprintf(stderr, "Could not run %s\n",
			    _PATH_SSH_USER_RC);
	} else if (stat(_PATH_SSH_SYSTEM_RC, &st) >= 0) {
		if (debug_flag)
			fprintf(stderr, "Running %s %s\n", _PATH_BSHELL,
			    _PATH_SSH_SYSTEM_RC);
		f = popen(_PATH_BSHELL " " _PATH_SSH_SYSTEM_RC, "w");
		if (f) {
			if (do_xauth)
				fprintf(f, "%s %s\n", s->auth_proto,
				    s->auth_data);
			pclose(f);
		} else
			fprintf(stderr, "Could not run %s\n",
			    _PATH_SSH_SYSTEM_RC);
	} else if (do_xauth && options.xauth_location != NULL) {
		/* Add authority data to .Xauthority if appropriate. */
		if (debug_flag) {
			fprintf(stderr,
			    "Running %.500s remove %.100s\n",
			    options.xauth_location, s->auth_display);
			fprintf(stderr,
			    "%.500s add %.100s %.100s %.100s\n",
			    options.xauth_location, s->auth_display,
			    s->auth_proto, s->auth_data);
		}
		snprintf(cmd, sizeof cmd, "%s -q -",
		    options.xauth_location);
		f = popen(cmd, "w");
		if (f) {
			fprintf(f, "remove %s\n",
			    s->auth_display);
			fprintf(f, "add %s %s %s\n",
			    s->auth_display, s->auth_proto,
			    s->auth_data);
			pclose(f);
		} else {
			fprintf(stderr, "Could not run %s\n",
			    cmd);
		}
	}
}

This category addresses vulnerabilities caused by flawed access control mechanisms, where incorrect permission settings allow unauthorized users to access restricted resources.