Exploit Code: /*
* $Id: raptor_chown.c,v 1.1 2004/12/04 14:44:38 raptor Exp $
*
* raptor_chown.c - sys_chown missing DAC controls on Linux
* Copyright (c) 2004 Marco Ivaldi <raptor at 0xdeadbeef dot info>
*
* Unknown vulnerability in Linux kernel 2.x may allow local users to
* modify the group ID of files, such as NFS exported files in kernel
* 2.4 (CAN-2004-0497).
*
* "Basically, you can change the group of a file you don't own, but not
* of an SGID executable." -- Solar Designer (0dd)
*
* On Linux 2.6.x < 2.6.7-rc3 it's possible to change the group of files you
* don't own, even on local filesystems. This may allow a local attacker to
* perform a privilege escalation, e.g. through the following attack vectors:
*
* 1) Target /etc/shadow: on some distros (namely slackware 9.1 and debian
* 3.0, probably others) the shadow group has read access to it.
* 2) Target /dev/mem, /dev/kmem: read arbitrary memory contents.
* 3) Target /dev/hd*, /dev/sd*: read arbitrary data stored on disks.
* 4) Target /dev/tty*, /dev/pts*: snoop/execute arbitrary commands.
*
* Usage:
* $ gcc raptor_chown.c -o raptor_chown -Wall
* $ ./raptor_chown /etc/shadow
* [...]
* -rw-r----- 1 root users 500 Mar 25 12:27 /etc/shadow
*
* Vulnerable platforms:
* Linux 2.2.x (on nfs exported files, should be vuln) [untested]
* Linux 2.4.x < 2.4.27-rc3 (on nfs exported files) [tested]
* Linux 2.6.x < 2.6.7-rc3 (default configuration) [tested]
*/