Release notes are available at https://www.openssh.com/txt/release-9.2
OpenSSH 9.2 contains fixes for two security problems and a memory safety
problem. The memory safety problem is not believed to be exploitable.
These fixes have already been committed to OpenSSH 9.1 in FreeBSD.
Some other notable items from the release notes:
* ssh(1): add a new EnableEscapeCommandline ssh_config(5) option that
controls whether the client-side ~C escape sequence that provides a
command-line is available. Among other things, the ~C command-line
could be used to add additional port-forwards at runtime.
* sshd(8): add support for channel inactivity timeouts via a new
sshd_config(5) ChannelTimeout directive. This allows channels that
have not seen traffic in a configurable interval to be
automatically closed. Different timeouts may be applied to session,
X11, agent and TCP forwarding channels.
* sshd(8): add a sshd_config UnusedConnectionTimeout option to
terminate client connections that have no open channels for a
length of time. This complements the ChannelTimeout option above.
* sshd(8): add a -V (version) option to sshd like the ssh client has.
* scp(1), sftp(1): add a -X option to both scp(1) and sftp(1) to
allow control over some SFTP protocol parameters: the copy buffer
length and the number of in-flight requests, both of which are used
during upload/download. Previously these could be controlled in
sftp(1) only. This makes them available in both SFTP protocol
clients using the same option character sequence.
* ssh-keyscan(1): allow scanning of complete CIDR address ranges,
e.g. "ssh-keyscan 192.168.0.0/24". If a CIDR range is passed, then
it will be expanded to all possible addresses in the range
including the all-0s and all-1s addresses. bz#976
* ssh(1): support dynamic remote port forwarding in escape
command-line's -R processing. bz#3499
MFC after: 1 week
Sponsored by: The FreeBSD Foundation
Release notes are available at https://www.openssh.com/txt/release-8.9
Some highlights:
* ssh(1), sshd(8), ssh-add(1), ssh-agent(1): add a system for
restricting forwarding and use of keys added to ssh-agent(1)
* ssh(1), sshd(8): add the sntrup761x25519-sha512@openssh.com hybrid
ECDH/x25519 + Streamlined NTRU Prime post-quantum KEX to the
default KEXAlgorithms list (after the ECDH methods but before the
prime-group DH ones). The next release of OpenSSH is likely to
make this key exchange the default method.
* sshd(8), portable OpenSSH only: this release removes in-built
support for MD5-hashed passwords. If you require these on your
system then we recommend linking against libxcrypt or similar.
Future deprecation notice
=========================
A near-future release of OpenSSH will switch scp(1) from using the
legacy scp/rcp protocol to using SFTP by default.
Legacy scp/rcp performs wildcard expansion of remote filenames (e.g.
"scp host:* .") through the remote shell. This has the side effect of
requiring double quoting of shell meta-characters in file names
included on scp(1) command-lines, otherwise they could be interpreted
as shell commands on the remote side.
MFC after: 1 month
Relnotes: Yes
Sponsored by: The FreeBSD Foundation
Some notable changes, from upstream's release notes:
- sshd(8): Remove support for obsolete "host/port" syntax.
- ssh(1): When prompting whether to record a new host key, accept the key
fingerprint as a synonym for "yes".
- ssh-keygen(1): when acting as a CA and signing certificates with an RSA
key, default to using the rsa-sha2-512 signature algorithm.
- ssh(1), sshd(8), ssh-keygen(1): this release removes the "ssh-rsa"
(RSA/SHA1) algorithm from those accepted for certificate signatures.
- ssh-sk-helper(8): this is a new binary. It is used by the FIDO/U2F
support to provide address-space isolation for token middleware
libraries (including the internal one).
- ssh(1): this release enables UpdateHostkeys by default subject to some
conservative preconditions.
- scp(1): this release changes the behaviour of remote to remote copies
(e.g. "scp host-a:/path host-b:") to transfer through the local host
by default.
- scp(1): experimental support for transfers using the SFTP protocol as
a replacement for the venerable SCP/RCP protocol that it has
traditionally used.
Additional integration work is needed to support FIDO/U2F in the base
system.
Deprecation Notice
------------------
OpenSSH will disable the ssh-rsa signature scheme by default in the
next release.
Reviewed by: imp
MFC after: 1 month
Relnotes: Yes
Sponsored by: The FreeBSD Foundation
Differential Revision: https://reviews.freebsd.org/D29985
I have worked hard to reduce diffs against the vendor branch. One
notable change in that respect is that we no longer prefer DSA over
RSA - the reasons for doing so went away years ago. This may cause
some surprises, as ssh will warn about unknown host keys even for
hosts whose keys haven't changed.
MFC after: 6 weeks
