Warning on weak keys and random numbers

Regarding the recently discovered random number vulnerability:

CAcert’s root keys are not affected, since they were created before the bug existed.
CAcert’s internal systems were affected, and are currently being cleaned up.
A lot of our users are affected.
We are currently working on improved methods to detect the vulnerabilities and inform the affected users about them.
In general, digital signatures and certificates are only affected in the case the any of the underlying keys are compromised. Signatures and certificates do not contain any additional random numbers, so they can’t be affected on their own, if the keys are not compromised.

We currently think that the articles in the media hasn’t informed everyone about the whole impact of the problem yet.

The affected distributions contain Debian, Ubuntu, Kubuntu, Knoppix, Grml, and various other Debian based distributions.
Also various embedded systems that are based on Debian are likely affected.

Regarding the applications, OpenSSL, OpenVPN, OpenXPKI, OpenCA, OpenSSH (especially client authorisation keys!), boxbackup and various other software packages are affected.

All systems that are relying on keys that were generated on affected systems are affected.
This means that you should scan all your SuSE, Fedora, Redhat, BSD, … SSH-servers for compromised keys in the authorized keys files of all users, and blacklist the compromised keys accordingly. (And the same for any other services that might rely on the compromised keys.)

If you want to assess the quality of your own random number generator, you can use our free service here:

We are currently developing a X.509 vulnerability detection system, which will be available for all CA’s, to discover similarly compromised keys as early as possible. If you want to participate and help there, please contact us.

Message to all non-Debian-derived vendors: Please ship blacklists and blacklist-detection software in your security updates. (Port ssh-vuln to your distribution, …) And warn your users too, not to rely on compromised keys anymore.

General information about the vulnerability:


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