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OpenSSH 7.0 Released

Posted by Soulskill on from the onward-and-upward dept.

An anonymous reader writes: Today the OpenSSH project maintainers announced the release of version 7.0. This release is focusing on deprecating weak and unsafe cryptographic methods, though some of the work won't be complete until 7.1. This release removes support for the following: the legacy SSH v1 protocol, the 1024-bit diffie-hellman-group1-sha1 key exchange, ssh-dss, ssh-dss-cert-* host and user keys, and legacy v00 cert format. There were also several bug fixes, security tweaks, and new features. In the next release, they plan to retire more legacy cryptography. This includes refusing RSA keys smaller than 1024 bits, disabling MD5-based HMAC algorithms, and disabling these ciphers: blowfish-cbc, cast128-cbc, all arcfour variants and the rijndael-cbc aliases for AES.

3 of 75 comments (clear)

  1. none cipher? by Anonymous Coward · · Score: 5, Interesting

    I hope they add a "none" cipher.

    I use ssh for X11 forwarding and encryption really slows it down. Currently I'm using arcfour because it's the fastest one. But TFS says that's going away in 7.1. Guess it's time to look for a patch.

    No, I don't want encryption between these machines. I would run "xhost +", but setting $DISPLAY after a script remotely logs in is ugly. " ssh -Y" makes it so much easier, cleaner, and more likely to be correct.

    1. Re:none cipher? by bill_mcgonigle · · Score: 4, Interesting

      Are you running old hardware? I've switched over to "-c aes128-ctr" for the best speed/security/compatibility compromise, but I have hardware AES. I get about a gigabit between vm's.

      ssh -c aes128-ctr -o Compression=no hostname cat /dev/zero |pv | cat > /dev/null

      on Intel(R) Xeon(R) CPU E5-2620 0 @ 2.00GHz

      --
      My God, it's Full of Source!
      OUTSIDE_IP=$(dig +short my.ip @outsideip.net)
    2. Re:none cipher? by hankwang · · Score: 4, Interesting

      in 2015 you must be running unbelievably shitty old hardware to even notice any slowdown any more with the best ciphers.

      Does running rsync on an Android phone or a low-end NAS qualify? I prefer to keep my backups local rather than in the cloud. I've said it before: The weaknesses in RC4/arcfour are all about leaking key information in the first 256 or maybe 512 bytes of cipher stream, because that's how long it takes to scramble the internal state. SSH always discards the first 1.5 kiB, so it's not vulnerable to this kind of attack. Why deprecate it?

      --
      Avantslash: low-bandwidth mobile slashdot.