USN-670-1: VMBuilder vulnerability

Releases

• Ubuntu 8.10
• Ubuntu 8.04
• Ubuntu 7.10
• Ubuntu 6.06

Packages

• shadow -
• vm-builder -

Details

Mathias Gug discovered that vm-builder improperly set the root
password when creating virtual machines. An attacker could exploit
this to gain root privileges to the virtual machine by using a
predictable password.

This vulnerability only affects virtual machines created with
vm-builder under Ubuntu 8.10, and does not affect native Ubuntu
installations. An update was made to the shadow package to detect
vulnerable systems and disable password authentication for the
root account. Vulnerable virtual machines which an attacker has
access to should be considered compromised, and appropriate actions
taken to secure the machine.

Update instructions

The problem can be corrected by updating your system to the following package versions:

Ubuntu 8.10

• passwd - 1:4.1.1-1ubuntu1.1
• python-vm-builder - 0.9-0ubuntu3.1

Ubuntu 8.04

• passwd - 1:4.0.18.2-1ubuntu2.1

Ubuntu 7.10

• passwd - 1:4.0.18.1-9ubuntu0.1

Ubuntu 6.06

• passwd - 1:4.0.13-7ubuntu3.3

In general, a standard system upgrade is sufficient to effect the
necessary changes.

References

• https://bugs.launchpad.net/+bug/296841