Vigil@nce: Xen, access to /local/domain
December 2008 by Vigil@nce
An attacker located in a guest system can write to some files of
/local/domain.
– Gravity: 1/4
– Consequences: data creation/edition, denial of service of service
– Provenance: user account
– Means of attack: no proof of concept, no attack
– Ability of attacker: expert (4/4)
– Confidence: confirmed by the editor (5/5)
– Diffusion of the vulnerable configuration: high (3/3)
– Creation date: 19/12/2008
IMPACTED PRODUCTS
– Citrix XenServer
– Unix - plateform
DESCRIPTION
The Xen /local/domain path contains information files:
/local/domain/(id)/vm
/local/domain/(id)/cpu
/local/domain/(id)/console/vnc-port
/local/domain/(id)/console/tty
etc.
Due to a restriction error, an attacker in a guest system can
write in some of these files.
An attacker can for example write to /local/domain/(id)/console/tty
in order to change the tty path. The administrator then connects
to the bad tty. If the tty name is invalid, the administrator
cannot connect to it.
This vulnerability can therefore lead to a denial of service.
CHARACTERISTICS
– Identifiers: 464817, CVE-2008-4405, VIGILANCE-VUL-8346
– Url: http://vigilance.fr/vulnerability/8346