Ubuntu Security Notice USN-355-1
2nd October, 2006
A security issue affects these releases of Ubuntu and its derivatives:
- Ubuntu 6.06 LTS
- Ubuntu 5.10
- Ubuntu 5.04
Tavis Ormandy discovered that the SSH daemon did not properly handle
authentication packets with duplicated blocks. By sending specially
crafted packets, a remote attacker could exploit this to cause the ssh
daemon to drain all available CPU resources until the login grace time
Mark Dowd discovered a race condition in the server's signal handling.
A remote attacker could exploit this to crash the server.
The problem can be corrected by updating your system to the following package version:
- Ubuntu 6.06 LTS:
- openssh-server 1:4.2p1-7ubuntu3.1
- Ubuntu 5.10:
- openssh-server 1:4.1p1-7ubuntu4.2
- Ubuntu 5.04:
- openssh-server 1:3.9p1-1ubuntu2.3
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