OpenSSH 7.6 was released on 2017-10-03. It is available from the mirrors listed at https://www.openssh.com/. OpenSSH is a 100% complete SSH protocol 2.0 implementation and includes sftp client and server support. Once again, we would like to thank the OpenSSH community for their continued support of the project, especially those who contributed code or patches, reported bugs, tested snapshots or donated to the project. More information on donations may be found at: http://www.openssh.com/donations.html Potentially-incompatible changes ================================ This release includes a number of changes that may affect existing configurations: * ssh(1): delete SSH protocol version 1 support, associated configuration options and documentation. * ssh(1)/sshd(8): remove support for the hmac-ripemd160 MAC. * ssh(1)/sshd(8): remove support for the arcfour, blowfish and CAST ciphers. * Refuse RSA keys <1024 bits in length and improve reporting for keys that do not meet this requirement. * ssh(1): do not offer CBC ciphers by default. Changes since OpenSSH 7.5 ========================= This is primarily a bugfix release. It also contains substantial internal refactoring. Security -------- * sftp-server(8): in read-only mode, sftp-server was incorrectly permitting creation of zero-length files. Reported by Michal Zalewski. New Features ------------ * ssh(1): add RemoteCommand option to specify a command in the ssh config file instead of giving it on the client's command line. This allows the configuration file to specify the command that will be executed on the remote host. * sshd(8): add ExposeAuthInfo option that enables writing details of the authentication methods used (including public keys where applicable) to a file that is exposed via a $SSH_USER_AUTH environment variable in the subsequent session. * ssh(1): add support for reverse dynamic forwarding. In this mode, ssh will act as a SOCKS4/5 proxy and forward connections to destinations requested by the remote SOCKS client. This mode is requested using extended syntax for the -R and RemoteForward options and, because it is implemented solely at the client, does not require the server be updated to be supported. * sshd(8): allow LogLevel directive in sshd_config Match blocks; bz#2717 * ssh-keygen(1): allow inclusion of arbitrary string or flag certificate extensions and critical options. * ssh-keygen(1): allow ssh-keygen to use a key held in ssh-agent as a CA when signing certificates. bz#2377 * ssh(1)/sshd(8): allow IPQoS=none in ssh/sshd to not set an explicit ToS/DSCP value and just use the operating system default. * ssh-add(1): added -q option to make ssh-add quiet on success. * ssh(1): expand the StrictHostKeyChecking option with two new settings. The first "accept-new" will automatically accept hitherto-unseen keys but will refuse connections for changed or invalid hostkeys. This is a safer subset of the current behaviour of StrictHostKeyChecking=no. The second setting "off", is a synonym for the current behaviour of StrictHostKeyChecking=no: accept new host keys, and continue connection for hosts with incorrect hostkeys. A future release will change the meaning of StrictHostKeyChecking=no to the behaviour of "accept-new". bz#2400 * ssh(1): add SyslogFacility option to ssh(1) matching the equivalent option in sshd(8). bz#2705 Bugfixes -------- * ssh(1): use HostKeyAlias if specified instead of hostname for matching host certificate principal names; bz#2728 * sftp(1): implement sorting for globbed ls; bz#2649 * ssh(1): add a user@host prefix to client's "Permission denied" messages, useful in particular when using "stacked" connections (e.g. ssh -J) where it's not clear which host is denying. bz#2720 * ssh(1): accept unknown EXT_INFO extension values that contain \0 characters. These are legal, but would previously cause fatal connection errors if received. * ssh(1)/sshd(8): repair compression statistics printed at connection exit * sftp(1): print '?' instead of incorrect link count (that the protocol doesn't provide) for remote listings. bz#2710 * ssh(1): return failure rather than fatal() for more cases during session multiplexing negotiations. Causes the session to fall back to a non-mux connection if they occur. bz#2707 * ssh(1): mention that the server may send debug messages to explain public key authentication problems under some circumstances; bz#2709 * Translate OpenSSL error codes to better report incorrect passphrase errors when loading private keys; bz#2699 * sshd(8): adjust compatibility patterns for WinSCP to correctly identify versions that implement only the legacy DH group exchange scheme. bz#2748 * ssh(1): print the "Killed by signal 1" message only at LogLevel verbose so that it is not shown at the default level; prevents it from appearing during ssh -J and equivalent ProxyCommand configs. bz#1906, bz#2744 * ssh-keygen(1): when generating all hostkeys (ssh-keygen -A), clobber existing keys if they exist but are zero length. zero-length keys could previously be made if ssh-keygen failed or was interrupted part way through generating them. bz#2561 * ssh(1): fix pledge(2) violation in the escape sequence "~&" used to place the current session in the background. * ssh-keyscan(1): avoid double-close() on file descriptors; bz#2734 * sshd(8): avoid reliance on shared use of pointers shared between monitor and child sshd processes. bz#2704 * sshd_config(8): document available AuthenticationMethods; bz#2453 * ssh(1): avoid truncation in some login prompts; bz#2768 * sshd(8): Fix various compilations failures, inc bz#2767 * ssh(1): make "--" before the hostname terminate argument processing after the hostname too. * ssh-keygen(1): switch from aes256-cbc to aes256-ctr for encrypting new-style private keys. Fixes problems related to private key handling for no-OpenSSL builds. bz#2754 * ssh(1): warn and do not attempt to use keys when the public and private halves do not match. bz#2737 * sftp(1): don't print verbose error message when ssh disconnects from under sftp. bz#2750 * sshd(8): fix keepalive scheduling problem: activity on a forwarded port from preventing the keepalive from being sent; bz#2756 * sshd(8): when started without root privileges, don't require the privilege separation user or path to exist. Makes running the regression tests easier without touching the filesystem. * Make integrity.sh regression tests more robust against timeouts. bz#2658 * ssh(1)/sshd(8): correctness fix for channels implementation: accept channel IDs greater than 0x7FFFFFFF. Portability ----------- * sshd(9): drop two more privileges in the Solaris sandbox: PRIV_DAX_ACCESS and PRIV_SYS_IB_INFO; bz#2723 * sshd(8): expose list of completed authentication methods to PAM via the SSH_AUTH_INFO_0 PAM environment variable. bz#2408 * ssh(1)/sshd(8): fix several problems in the tun/tap forwarding code, mostly to do with host/network byte order confusion. bz#2735 * Add --with-cflags-after and --with-ldflags-after configure flags to allow setting CFLAGS/LDFLAGS after configure has completed. These are useful for setting sanitiser/fuzzing options that may interfere with configure's operation. * sshd(8): avoid Linux seccomp violations on ppc64le over the socketcall syscall. * Fix use of ldns when using ldns-config; bz#2697 * configure: set cache variables when cross-compiling. The cross- compiling fallback message was saying it assumed the test passed, but it wasn't actually set the cache variables and this would cause later tests to fail. * Add clang libFuzzer harnesses for public key parsing and signature verification. Checksums: ========== - SHA1 (openssh-7.6.tar.gz) = 157fe3989a245c58fcdb34d9fe722a3c4e14c008 - SHA1 (openssh-7.6p1.tar.gz) = a6984bc2c72192bed015c8b879b35dd9f5350b3b - SHA256 (openssh-7.6.tar.gz) = Xu3bdpCcu65vM2FnW7b6IKLgd4Kvf2P3WBTMw+I7Bao= - SHA256 (openssh-7.6p1.tar.gz) = oyPK7t3+FFuqoNsW6Y14Sx+8fdQ2pr8fR539XNHSFyM= Please note that the SHA256 signatures are base64 encoded and not hexadecimal (which is the default for most checksum tools). The PGP key used to sign the releases is available as RELEASE_KEY.asc from the mirror sites. Reporting Bugs: =============== - Please read http://www.openssh.com/report.html Security bugs should be reported directly to openssh@openssh.com OpenSSH is brought to you by Markus Friedl, Niels Provos, Theo de Raadt, Kevin Steves, Damien Miller, Darren Tucker, Jason McIntyre, Tim Rice and Ben Lindstrom.