Ubuntu 8.10 / 9.04 / 9.10 : dhcp3 vulnerability (USN-803-2)

Ubuntu Security Notice (C) 2010-2016 Canonical, Inc. / NASL script (C) 2010-2016 Tenable Network Security, Inc.


Synopsis :

The remote Ubuntu host is missing one or more security-related
patches.

Description :

USN-803-1 fixed a vulnerability in Dhcp. Due to an error, the patch to
fix the vulnerability was not properly applied on Ubuntu 8.10 and
higher. Even with the patch improperly applied, the default compiler
options reduced the vulnerability to a denial of service.
Additionally, in Ubuntu 9.04 and higher, users were also protected by
the AppArmor dhclient3 profile. This update fixes the problem.

It was discovered that the DHCP client as included in dhcp3 did not
verify the length of certain option fields when processing a response
from an IPv4 dhcp server. If a user running Ubuntu 6.06 LTS or 8.04
LTS connected to a malicious dhcp server, a remote attacker could
cause a denial of service or execute arbitrary code as the user
invoking the program, typically the 'dhcp' user. For users running
Ubuntu 8.10 or 9.04, a remote attacker should only be able to cause a
denial of service in the DHCP client. In Ubuntu 9.04, attackers would
also be isolated by the AppArmor dhclient3 profile.

Note that Tenable Network Security has extracted the preceding
description block directly from the Ubuntu security advisory. Tenable
has attempted to automatically clean and format it as much as possible
without introducing additional issues.

Solution :

Update the affected packages.

Risk factor :

Critical / CVSS Base Score : 10.0
(CVSS2#AV:N/AC:L/Au:N/C:C/I:C/A:C)
CVSS Temporal Score : 8.7
(CVSS2#E:ND/RL:OF/RC:C)
Public Exploit Available : true

Family: Ubuntu Local Security Checks

Nessus Plugin ID: 44326 ()

Bugtraq ID: 35668

CVE ID: CVE-2009-0692