Ubuntu Security Notice USN-612-11

18th June, 2008

openssl-blacklist update

A security issue affects these releases of Ubuntu and its derivatives:

• Ubuntu 8.04 LTS
• Ubuntu 7.10
• Ubuntu 7.04
• Ubuntu 6.06 LTS

Software description

• openssl-blacklist

Details

USN-612-3 addressed a weakness in OpenSSL certificate and key
generation and introduced openssl-blacklist to aid in detecting
vulnerable certificates and keys. This update adds RSA-4096
blacklists to the openssl-blacklist-extra package and adjusts
openssl-vulnkey to properly handle RSA-4096 and higher moduli.

Original advisory details:
A weakness has been discovered in the random number generator used
by OpenSSL on Debian and Ubuntu systems. As a result of this
weakness, certain encryption keys are much more common than they
should be, such that an attacker could guess the key through a
brute-force attack given minimal knowledge of the system. This
particularly affects the use of encryption keys in OpenSSH, OpenVPN
and SSL certificates.

Update instructions

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

Ubuntu 8.04 LTS:

openssl-blacklist 0.3.3+0.4-0ubuntu0.8.04.3

openssl-blacklist-extra 0.3.3+0.4-0ubuntu0.8.04.3

Ubuntu 7.10:

openssl-blacklist 0.3.3+0.4-0ubuntu0.7.10.2

openssl-blacklist-extra 0.3.3+0.4-0ubuntu0.7.10.2

Ubuntu 7.04:

openssl-blacklist 0.3.3+0.4-0ubuntu0.7.04.2

openssl-blacklist-extra 0.3.3+0.4-0ubuntu0.7.04.2

Ubuntu 6.06 LTS:

openssl-blacklist 0.3.3+0.4-0ubuntu0.6.06.2

openssl-blacklist-extra 0.3.3+0.4-0ubuntu0.6.06.2

To update your system, please follow these instructions: https://wiki.ubuntu.com/Security/Upgrades.

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

References

http://www.ubuntu.com/usn/usn-612-1, http://www.ubuntu.com/usn/usn-612-3, http://www.ubuntu.com/usn/usn-612-8, http://www.ubuntu.com/usn/usn-612-9