- [Feature]: Transport grew a new packetizer_class kwarg for
overriding the packet-handler class used internally. Mostly for
testing, but advanced users may find this useful when doing deep
hacks.
- [Bug]: Tweak ext-info-(c|s) detection during KEXINIT protocol
phase; the original implementation made assumptions based on an
OpenSSH implementation detail.
- [Bug]: Address CVE 2023-48795 (aka the “Terrapin Attack”, a
vulnerability found in the SSH protocol re: treatment of packet
sequence numbers) as follows:
- The vulnerability only impacts encrypt-then-MAC digest
algorithms in tandem with CBC ciphers, and ChaCha20-poly1305;
of these, Paramiko currently only implements
hmac-sha2-(256|512)-etm in tandem with AES-CBC. If you are
unable to upgrade to Paramiko versions containing the below
fixes right away, you may instead use the disabled_algorithms
connection option to disable the ETM MACs and/or the CBC
ciphers (this option is present in Paramiko >=2.6).
- As the fix for the vulnerability requires both ends of the
connection to cooperate, the below changes will only take effect
when the remote end is OpenSSH >= 9.6 (or equivalent, such as
Paramiko in server mode, as of this patch version) and configured
to use the new “strict kex” mode. Paramiko will always attempt to
use “strict kex” mode if offered by the server, unless you
override this by specifying strict_kex=False in Transport.__init__.
- Paramiko will now raise an SSHException subclass
(MessageOrderError) when protocol messages are received in
unexpected order. This includes situations like receiving MSG_DEBUG
or MSG_IGNORE during initial key exchange, which are no longer
allowed during strict mode.
- Key (re)negotiation – i.e. MSG_NEWKEYS, whenever it is
encountered – now resets packet sequence numbers. (This should be
invisible to users during normal operation, only causing exceptions
if the exploit is encountered, which will usually result in, again,
MessageOrderError.)
- Sequence number rollover will now raise SSHException if it occurs
during initial key exchange (regardless of strict mode status).
Signed-off-by: Javier Marcet <javier@marcet.info>
* Rename PYTHON3_PKG_SETUP_VARS to PYTHON3_PKG_BUILD_VARS, and
PYTHON3_PKG_SETUP_DIR to PYTHON3_PKG_BUILD_PATH
The new variable names emphasize that these values apply to the new
build process.
* Remove PYTHON3_PKG_SETUP_ARGS set to the empty string
These were set to override the default arguments in the old build
process and not applicable to the new build process.
Signed-off-by: Jeffery To <jeffery.to@gmail.com>
2.11.0:
- [Feature] Add SSH config token expansion (eg %h, %p) when parsing
ProxyJump directives. Patch courtesy of Bruno Inec.
- [Support] (via #2011) Apply unittest skipIf to tests currently
using SHA1 in their critical path, to avoid failures on systems
starting to disable SHA1 outright in their crypto backends (eg RHEL
9). Report & patch via Paul Howarth.
- [Support] Update camelCase method calls against the threading
module to be snake_case; this and related tweaks should fix some
deprecation warnings under Python 3.10. Thanks to Karthikeyan
Singaravelan for the report, @Narendra-Neerukonda for the patch,
and to Thomas Grainger and Jun Omae for patch workshopping.
- [Support] Recent versions of Cryptography have deprecated Blowfish
algorithm support; in lieu of an easy method for users to remove it
from the list of algorithms Paramiko tries to import and use, we’ve
decided to remove it from our “preferred algorithms” list. This will
both discourage use of a weak algorithm, and avoid warnings. Credit
for report/patch goes to Mike Roest.
2.10.5:
- [Bug] Windows-native SSH agent support as merged in 2.10 could
encounter Errno 22 OSError exceptions in some scenarios (eg server
not cleanly closing a relevant named pipe). This has been worked
around and should be less problematic. Reported by Danilo Campana
Fuchs and patched by Jun Omae.
- [Bug] OpenSSH 7.7 and older has a bug preventing it from
understanding how to perform SHA2 signature verification for RSA
certificates (specifically certs - not keys), so when we added SHA2
support it broke all clients using RSA certificates with these
servers. This has been fixed in a manner similar to what OpenSSH’s
own client does: a version check is performed and the algorithm used
is downgraded if needed. Reported by Adarsh Chauhan, with fix
suggested by Jun Omae.
- [Bug] Align signature verification algorithm with OpenSSH re:
zero-padding signatures which don’t match their nominal size/length.
This shouldn’t affect most users, but will help Paramiko-implemented
SSH servers handle poorly behaved clients such as PuTTY. Thanks to
Jun Omae for catch & patch.
Signed-off-by: Javier Marcet <javier@marcet.info>
- [Bug] Servers offering certificate variants of hostkey algorithms
(eg ssh-rsa-cert-v01@openssh.com) could not have their host keys
verified by Paramiko clients, as it only ever considered non-cert key
types for that part of connection handshaking. This has been fixed.
- [Bug] PKey instances’ __eq__ did not have the usual safety guard in
place to ensure they were being compared to another PKey object,
causing occasional spurious BadHostKeyException (among other things).
This has been fixed. Thanks to Shengdun Hua for the original report
/patch and to Christopher Papke for the final version of the fix.
- [Support] Update camelCase method calls against the threading
module to be snake_case; this and related tweaks should fix some
deprecation warnings under Python 3.10. Thanks to Karthikeyan
Singaravelan for the report, @Narendra-Neerukonda for the patch, and
to Thomas Grainger and Jun Omae for patch workshopping.
Signed-off-by: Javier Marcet <javier@marcet.info>
2.10.2:
- [Bug] Fix Python 2 compatibility breakage introduced in 2.10.1.
Spotted by Christian Hammond.
2.10.3:
- [Bug] Switch from module-global to thread-local storage when
recording thread IDs for a logging helper; this should avoid one
flavor of memory leak for long-running processes. Catch & patch via
Richard Kojedzinszky.
- [Bug] Certificate-based pubkey auth was inadvertently broken when
adding SHA2 support; this has been fixed. Reported by Erik Forsberg
and fixed by Jun Omae.
Signed-off-by: Javier Marcet <javier@marcet.info>
2.10.1:
- [Bug]: (CVE-2022-24302) Creation of new private key files using
PKey subclasses was subject to a race condition between file creation
& mode modification, which could be exploited by an attacker with
knowledge of where the Paramiko-using code would write out such
files.
- This has been patched by using os.open and os.fdopen to ensure new
files are opened with the correct mode immediately. We’ve left the
subsequent explicit chmod in place to minimize any possible
disruption, though it may get removed in future backwards-
incompatible updates.
- Thanks to Jan Schejbal for the report & feedback on the solution,
and to Jeremy Katz at Tidelift for coordinating the disclosure.
2.10.0:
- [Feature] Add support for OpenSSH’s Windows agent as a fallback
when Putty/WinPageant isn’t available or functional. Reported by
@benj56 with patches/PRs from @lewgordon and Patrick Spendrin.
- [Feature] Add support for the %C token when parsing SSH config
files. Foundational PR submitted by @jbrand42.
- [Bug] Significantly speed up low-level read/write actions on
SFTPFile objects by using bytearray/memoryview. This is unlikely to
change anything for users of the higher level methods like
SFTPClient.get or SFTPClient.getfo, but users of SFTPClient.open will
likely see orders of magnitude improvements for files larger than a
few megabytes in size.
- Thanks to @jkji for the original report and to Sevastian Tchernov
for the patch.
- [Support] Add six explicitly to install-requires; it snuck into
active use at some point but has only been indicated by transitive
dependency on bcrypt until they somewhat-recently dropped it. This
will be short-lived until we drop Python 2 support. Thanks to
Sondre Lillebø Gundersen for catch & patch.
Signed-off-by: Javier Marcet <javier@marcet.info>
- [Bug]: Enhanced log output when connecting to servers that do not
support server-sig-algs extensions, making the new-as-of-2.9
defaulting to SHA2 pubkey algorithms more obvious when it kicks in.
- [Bug]: Connecting to servers which support server-sig-algs but
which have no overlap between that list and what a Paramiko client
supports, now raise an exception instead of defaulting to
rsa-sha2-512 (since the use of server-sig-algs allows us to know
what the server supports).
Signed-off-by: Javier Marcet <javier@marcet.info>
