Ubuntu Security Notice USN-1197-6
September 22, 2011
A security issue affects these releases of Ubuntu and its derivatives:
- Ubuntu 11.04
- Ubuntu 10.10
- Ubuntu 10.04 LTS
A certificate authority mis-issued fraudulent certificates.
- qt4-x11: Qt 4 libraries and support modules
USN-1197-1 and USN-1197-3 addressed an issue in Firefox and Xulrunner
pertaining to the Dutch Certificate Authority DigiNotar mis-issuing
fraudulent certificates. This update provides an update
for Qt that blacklists the known fraudulent certificates.
Original advisory details:
It was discovered that Dutch Certificate Authority DigiNotar had
mis-issued multiple fraudulent certificates. These certificates could allow
an attacker to perform a "man in the middle" (MITM) attack which would make
the user believe their connection is secure, but is actually being
For the protection of its users, Mozilla has removed the DigiNotar
certificate. Sites using certificates issued by DigiNotar will need to seek
another certificate vendor.
We are currently aware of a regression that blocks one of two Staat der
Nederlanden root certificates which are believed to still be secure. This
regression is being tracked at https://launchpad.net/bugs/838322.
USN-1197-1 partially addressed an issue with Dutch Certificate Authority
DigiNotar mis-issuing fraudulent certificates. This update actively
distrusts the DigiNotar root certificate as well as several intermediary
certificates. Also included in this list of distrusted certificates are the
"PKIOverheid" (PKIGovernment) intermediates under DigiNotar's control that
did not chain to DigiNotar's root and were not previously blocked.
The problem can be corrected by updating your system to the following
Ubuntu 10.04 LTS:
After a standard system upgrade you need to restart your session to effect
the necessary changes.