>From the OpenBSD change logs:
RCS file: /cvs/src/sys/kern/vfs_syscalls.c,v
----------------------------
revision 1.59
date: 1999/07/30 18:27:47; author: deraadt; state: Exp; lines: +20 -1
do not permit regular users to chflags/fchflags on chr or blk devices --
even if they happen to own them at the moment.
NetBSD-current has this fixed as of the following revision of
vfs_syscalls.c.
$NetBSD: vfs_syscalls.c,v 1.146 1999/07/31 03:18:43 christos
>From quick inspection, FreeBSD appears to be vulnerable.
