Changelog
openssh (1:9.6p1-1) unstable; urgency=medium
* Use single quotes in suggested ssh-keygen commands (closes: #1057835).
* Debconf translations:
- Catalan (thanks, Pablo Huguet; closes: #1049995).
* New upstream release (https://www.openssh.com/releasenotes.html#9.6p1):
- [CVE-2023-48795] ssh(1), sshd(8): implement protocol extensions to
thwart the so-called "Terrapin attack" discovered by Fabian Bäumer,
Marcus Brinkmann and Jörg Schwenk. This attack allows a MITM to effect
a limited break of the integrity of the early encrypted SSH transport
protocol by sending extra messages prior to the commencement of
encryption, and deleting an equal number of consecutive messages
immediately after encryption starts. A peer SSH client/server would
not be able to detect that messages were deleted.
- [SECURITY] ssh-agent(1): when adding PKCS#11-hosted private keys while
specifying destination constraints, if the PKCS#11 token returned
multiple keys then only the first key had the constraints applied. Use
of regular private keys, FIDO tokens and unconstrained keys are
unaffected.
- [SECURITY] ssh(1): if an invalid user or hostname that contained shell
metacharacters was passed to ssh(1), and a ProxyCommand, LocalCommand
directive or "match exec" predicate referenced the user or hostname
via %u, %h or similar expansion token, then an attacker who could
supply arbitrary user/hostnames to ssh(1) could potentially perform
command injection depending on what quoting was present in the
user-supplied ssh_config(5) directive. OpenSSH 9.6 now bans most shell
metacharacters from user and hostnames supplied via the command-line.
- ssh(1), sshd(8): the RFC4254 connection/channels protocol provides a
TCP-like window mechanism that limits the amount of data that can be
sent without acceptance from the peer. In cases where this limit was
exceeded by a non-conforming peer SSH implementation, ssh(1)/sshd(8)
previously discarded the extra data. From OpenSSH 9.6, ssh(1)/sshd(8)
will now terminate the connection if a peer exceeds the window limit
by more than a small grace factor. This change should have no effect
of SSH implementations that follow the specification.
- ssh(1): add a %j token that expands to the configured ProxyJump
hostname (or the empty string if this option is not being used) that
can be used in a number of ssh_config(5) keywords.
- ssh(1): add ChannelTimeout support to the client, mirroring the same
option in the server and allowing ssh(1) to terminate quiescent
channels.
- ssh(1), sshd(8), ssh-add(1), ssh-keygen(1): add support for reading
ED25519 private keys in PEM PKCS8 format. Previously only the OpenSSH
private key format was supported.
- ssh(1), sshd(8): introduce a protocol extension to allow renegotiation
of acceptable signature algorithms for public key authentication after
the server has learned the username being used for authentication.
This allows varying sshd_config(5) PubkeyAcceptedAlgorithms in a
"Match user" block.
- ssh-add(1), ssh-agent(1): add an agent protocol extension to allow
specifying certificates when loading PKCS#11 keys. This allows the use
of certificates backed by PKCS#11 private keys in all OpenSSH tools
that support ssh-agent(1). Previously only ssh(1) supported this
use-case.
- ssh(1): when deciding whether to enable the keystroke timing
obfuscation, enable it only if a channel with a TTY is active.
- ssh(1): switch mainloop from poll(3) to ppoll(3) and mask signals
before checking flags set in signal handler. Avoids potential race
condition between signaling ssh to exit and polling.
- ssh(1): when connecting to a destination with both the AddressFamily
and CanonicalizeHostname directives in use, the AddressFamily
directive could be ignored.
- sftp(1): correct handling of the <email address hidden> option when the
server returned an unexpected message.
- ssh(1): release GSS OIDs only at end of authentication, avoiding
unnecessary init/cleanup cycles.
- ssh_config(5): mention "none" is a valid argument to IdentityFile in
the manual.
- scp(1): improved debugging for paths from the server rejected for not
matching the client's glob(3) pattern in old SCP/RCP protocol mode.
- ssh-agent(1): refuse signing operations on destination-constrained
keys if a previous session-bind operation has failed. This may prevent
a fail-open situation in future if a user uses a mismatched ssh(1)
client and ssh-agent(1) where the client supports a key type that the
agent does not support.
* debian/run-tests: Supply absolute paths to tools.
* debian/run-tests: Enable interop tests for Dropbear.
-- Colin Watson <email address hidden> Mon, 18 Dec 2023 22:35:25 +0000
