Vigil@nce: sudo, group elevation
March 2010 by Vigil@nce
When the /etc/sudoers file contains "runas_default", a local
attacker can execute a command with privileges of root’s groups.
– Severity: 2/4
– Consequences: privileged access/rights
– Provenance: user shell
– 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: 23/02/2010
IMPACTED PRODUCTS
– Mandriva Enterprise Server
– Mandriva Linux
– Red Hat Enterprise Linux
– Unix - plateform
DESCRIPTION OF THE VULNERABILITY
The "runas_default" directive of the /etc/sudoers file defines a
default user. For example, if the file contains:
Defaults runas_default=test
the user can enter:
sudo command
instead of:
sudo -u test command
However, when this option is used, the user stays a member of
root’s groups (root, bin, daemon, sys, adm, disk, wheel), instead
of becoming a member of groups of user "test".
When the /etc/sudoers file contains "runas_default", a local
attacker can therefore execute a command with privileges of root’s
groups.
CHARACTERISTICS
– Identifiers: CVE-2010-0427, MDVSA-2010:052, RHSA-2010:0122-01,
VIGILANCE-VUL-9469
– Url: http://vigilance.fr/vulnerability/sudo-group-elevation-9469