Changes since OpenSSH 5.1
=========================
Security:
* This release changes the default cipher order to prefer the AES CTR
modes and the revised "arcfour256" mode to CBC mode ciphers that are
susceptible to CPNI-957037 "Plaintext Recovery Attack Against SSH".
* This release also adds countermeasures to mitigate CPNI-957037-style
attacks against the SSH protocol's use of CBC-mode ciphers. Upon
detection of an invalid packet length or Message Authentication
Code, ssh/sshd will continue reading up to the maximum supported
packet length rather than immediately terminating the connection.
This eliminates most of the known differences in behaviour that
leaked information about the plaintext of injected data which formed
the basis of this attack. We believe that these attacks are rendered
infeasible by these changes.
New features:
* Added a -y option to ssh(1) to force logging to syslog rather than
stderr, which is useful when running daemonised (ssh -f)
* The sshd_config(5) ForceCommand directive now accepts commandline
arguments for the internal-sftp server.
* The ssh(1) ~C escape commandline now support runtime creation of
dynamic (-D) port forwards.
* Support the SOCKS4A protocol in ssh(1) dynamic (-D) forwards.
(bz#1482)
* Support remote port forwarding with a listen port of '0'. This
informs the server that it should dynamically allocate a listen
port and report it back to the client. (bz#1003)
* sshd(8) now supports setting PermitEmptyPasswords and
AllowAgentForwarding in Match blocks
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