USN-355-1: openssh vulnerabilities

2 October 2006

openssh vulnerabilities

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Releases

Details

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
expired. (CVE-2006-4924)

Mark Dowd discovered a race condition in the server's signal handling.
A remote attacker could exploit this to crash the server.
(CVE-2006-5051)

Reduce your security exposure

Ubuntu Pro provides ten-year security coverage to 25,000+ packages in Main and Universe repositories, and it is free for up to five machines.

Learn more about Ubuntu Pro

Update instructions

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

Ubuntu 6.06
  • 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

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