USN-1197-5: CA Certificates vulnerability

9 September 2011

ca-certificates vulnerability

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.

Software Description

  • ca-certificates - Common CA certificates


USN-1197-1 addressed an issue in Firefox and Xulrunner pertaining to the Dutch Certificate Authority DigiNotar mis-issuing fraudulent certificates. This update provides the corresponding update for ca-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 monitored.

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

Update instructions

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

Ubuntu 11.04
ca-certificates - 20090814+nmu2ubuntu0.1
Ubuntu 10.10
ca-certificates - 20090814ubuntu0.10.10.1
Ubuntu 10.04 LTS
ca-certificates - 20090814ubuntu0.10.04.1

To update your system, please follow these instructions:

After a standard system update you need to restart any application using ca-certificates to make all the necessary changes.