Ubuntu Security Notice USN-1923-1
31st July, 2013
gnupg, libgcrypt11 vulnerability
A security issue affects these releases of Ubuntu and its derivatives:
- Ubuntu 13.04
- Ubuntu 12.10
- Ubuntu 12.04 LTS
- Ubuntu 10.04 LTS
GnuPG and Libgcrypt could be made to expose sensitive information.
- gnupg - GNU privacy guard - a free PGP replacement
- libgcrypt11 - LGPL Crypto library - runtime library
Yuval Yarom and Katrina Falkner discovered a timing-based information leak,
known as Flush+Reload, that could be used to trace execution in programs.
GnuPG and Libgcrypt followed different execution paths based on key-related
data, which could be used to expose the contents of private keys.
The problem can be corrected by updating your system to the following package version:
- Ubuntu 13.04:
- libgcrypt11 1.5.0-3ubuntu2.2
- gnupg 1.4.12-7ubuntu1.1
- Ubuntu 12.10:
- libgcrypt11 1.5.0-3ubuntu1.1
- gnupg 1.4.11-3ubuntu4.2
- Ubuntu 12.04 LTS:
- libgcrypt11 1.5.0-3ubuntu0.2
- gnupg 1.4.11-3ubuntu2.3
- Ubuntu 10.04 LTS:
- libgcrypt11 1.4.4-5ubuntu2.2
- gnupg 1.4.10-2ubuntu1.3
To update your system, please follow these instructions: https://wiki.ubuntu.com/Security/Upgrades.
In general, a standard system update will make all the necessary changes.