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Who When What Removed Added
Josh Bressers 2016-09-07 14:11:55 UTC CC bressers
Jakub Svoboda 2016-09-08 13:59:42 UTC CC jjelen
Flags needinfo?(jjelen)
Jakub Jelen 2016-09-15 07:53:11 UTC Blocks 1335911
Summary Ciphers and MACs enabled by default differ from upstream OpenSSH 6.7 with security implications. Remove RC4 cipher and questionable MACs enabled by default from OpenSSH
QA Contact qe-baseos-security szidek
Flags needinfo?(jjelen)
Muhammad Azhar Shaikh 2016-09-15 09:09:44 UTC CC mdshaikh
Tomas Mraz 2016-09-29 14:32:57 UTC CC thibaut.pouzet
CC tmraz
Nikos Mavrogiannopoulos 2016-11-01 17:15:37 UTC CC nmavrogi
Jakub Jelen 2016-11-01 17:16:18 UTC Status NEW ASSIGNED
Jakub Jelen 2016-11-02 11:48:59 UTC Status ASSIGNED MODIFIED
Fixed In Version openssh-5.3p1-120.el6
errata-xmlrpc 2016-11-02 12:02:38 UTC Status MODIFIED ON_QA
Stefan Dordevic 2016-11-14 12:56:01 UTC CC sdordevi
Flags needinfo?(jjelen)
Jakub Jelen 2016-11-14 13:04:57 UTC Flags needinfo?(jjelen)
Stanislav Zidek 2016-11-14 14:00:34 UTC Doc Type If docs needed, set a value Release Note
Jakub Jelen 2016-11-15 09:29:46 UTC Doc Text This release is deprecating old algorithms known to be broken from the default client configuration. The affected algorithms are `arcfour256,arcfour128,arcfour` ciphers and `hmac-md5,hmac-md5-96` MACs. This does not affect any existing server configuration.

If some of your connections depend on the above algorithms, you can re-enable them per-host in `ssh_config`, for example:

Host legacy
Ciphers arcfour
MACs hmac-md5

If you want to restore the previous functionality and use also the above configuration, you can add this snippet to the system-wide `/etc/ssh/ssh_config`:

Ciphers aes128-ctr,aes192-ctr,aes256-ctr,arcfour256,arcfour128,aes128-cbc,3des-cbc,blowfish-cbc,cast128-cbc,aes192-cbc,aes256-cbc,arcfour,rijndael-cbc@lysator.liu.se
MACs hmac-md5,hmac-sha1,umac-64@openssh.com,hmac-sha2-256,hmac-sha2-512,hmac-ripemd160,hmac-ripemd160@openssh.com,hmac-sha1-96,hmac-md5-96
Stanislav Zidek 2016-12-09 10:55:23 UTC QA Contact szidek sdordevi
Lenka Špačková 2016-12-12 11:15:48 UTC Docs Contact mjahoda
Stefan Dordevic 2016-12-12 13:22:17 UTC Flags needinfo?(jjelen)
Mirek Jahoda 2016-12-12 15:45:40 UTC Flags needinfo?(jjelen)
Nikos Mavrogiannopoulos 2016-12-13 15:34:29 UTC Doc Type Release Note Deprecated Functionality
Flags needinfo?(jjelen) needinfo?(jjelen)
errata-xmlrpc 2016-12-20 09:42:08 UTC Status ON_QA VERIFIED
Mirek Jahoda 2017-01-04 10:37:39 UTC Doc Text This release is deprecating old algorithms known to be broken from the default client configuration. The affected algorithms are `arcfour256,arcfour128,arcfour` ciphers and `hmac-md5,hmac-md5-96` MACs. This does not affect any existing server configuration.

If some of your connections depend on the above algorithms, you can re-enable them per-host in `ssh_config`, for example:

Host legacy
Ciphers arcfour
MACs hmac-md5

If you want to restore the previous functionality and use also the above configuration, you can add this snippet to the system-wide `/etc/ssh/ssh_config`:

Ciphers aes128-ctr,aes192-ctr,aes256-ctr,arcfour256,arcfour128,aes128-cbc,3des-cbc,blowfish-cbc,cast128-cbc,aes192-cbc,aes256-cbc,arcfour,rijndael-cbc@lysator.liu.se
MACs hmac-md5,hmac-sha1,umac-64@openssh.com,hmac-sha2-256,hmac-sha2-512,hmac-ripemd160,hmac-ripemd160@openssh.com,hmac-sha1-96,hmac-md5-96
Deprecated algorithms in *OpenSSH*: RC4, hmac-md5, and hmac-md5-96

With this update, the `arcfour256`, `arcfour128`, `arcfour` ciphers and the `hmac-md5`, `hmac-md5-96` Method Authentication Code (MAC) algorithms are deprecated. Note that this change does not affect any existing server configuration.

The system administrator can enable these deprecated algorithms by editing the `ssh_config` file, for example:

Host legacy
Ciphers arcfour
MACs hmac-md5

To completely restore the deprecated functionality, add the following snippet to the `/etc/ssh/ssh_config` file:

Ciphers aes128-ctr,aes192-ctr,aes256-ctr,arcfour256,arcfour128,aes128-cbc,3des-cbc,blowfish-cbc,cast128-cbc,aes192-cbc,aes256-cbc,arcfour,rijndael-cbc@lysator.liu.se
MACs hmac-md5,hmac-sha1,umac-64@openssh.com,hmac-sha2-256,hmac-sha2-512,hmac-ripemd160,hmac-ripemd160@openssh.com,hmac-sha1-96,hmac-md5-96
Jakub Jelen 2017-02-01 15:09:21 UTC CC leonard-rh-bugzilla
Alan Bartlett 2017-02-01 16:07:23 UTC CC ajb, ned
Alan Bartlett 2017-02-01 16:07:56 UTC CC toracat
errata-xmlrpc 2017-03-21 00:49:22 UTC Status VERIFIED RELEASE_PENDING
errata-xmlrpc 2017-03-21 10:02:38 UTC Status RELEASE_PENDING CLOSED
Resolution --- ERRATA
Last Closed 2017-03-21 06:02:38 UTC
Yasuhiro Ozone 2017-12-05 09:15:14 UTC CC yozone

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