Fri Jan 15 15:05:00 GMT 2016
I've just updated the Cygwin version of OpenSSH to 7.1p2-1.
This is a security upstream release.
Below's the original release message.
Please note that the release message has a bug :) The entry "SECURITY:
Eliminate the fallback from untrusted X11-forwarding ..." is wrong since
this change has been taken out of the 7.1p2 last-minute.
OpenSSH 7.1p2 has just been released. It will be available from the
mirrors listed at http://www.openssh.com/ shortly.
OpenSSH is a 100% complete SSH protocol 2.0 implementation and
includes sftp client and server support. OpenSSH also includes
transitional support for the legacy SSH 1.3 and 1.5 protocols
that may be enabled at compile-time.
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:
Changes since OpenSSH 7.1p1
* SECURITY: ssh(1): The OpenSSH client code between 5.4 and 7.1
contains experimential support for resuming SSH-connections (roaming).
The matching server code has never been shipped, but the client
code was enabled by default and could be tricked by a malicious
server into leaking client memory to the server, including private
client user keys.
The authentication of the server host key prevents exploitation
by a man-in-the-middle, so this information leak is restricted
to connections to malicious or compromised servers.
MITIGATION: For OpenSSH >= 5.4 the vulnerable code in the client
can be completely disabled by adding 'UseRoaming no' to the gobal
ssh_config(5) file, or to user configuration in ~/.ssh/config,
or by passing -oUseRoaming=no on the command line.
PATCH: See below for a patch to disable this feature (Disabling
Roaming in the Source Code).
This problem was reported by the Qualys Security Advisory team.
* SECURITY: Eliminate the fallback from untrusted X11-forwarding
to trusted forwarding for cases when the X server disables
the SECURITY extension. Reported by Thomas Hoger.
* SECURITY: Fix an out of-bound read access in the packet handling
code. Reported by Ben Hawkes.
* PROTOCOL: Correctly interpret the 'first_kex_follows' option during
the intial key exchange. Reported by Matt Johnston.
* Further use of explicit_bzero has been added in various buffer
handling code paths to guard against compilers aggressively
doing dead-store removal.
- SHA1 (openssh-7.1p2.tar.gz) = 9202f5a2a50c8a55ecfb830609df1e1fde97f758
- SHA256 (openssh-7.1p2.tar.gz) = dd75f024dcf21e06a0d6421d582690bf987a1f6323e32
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.
- Please read http://www.openssh.com/report.html
Security bugs should be reported directly to firstname.lastname@example.org
OpenSSH is brought to you by Markus Friedl, Niels Provos, Theo de Raadt,
Kevin Steves, Damien Miller, Darren Tucker, Jason McIntyre, Tim Rice and
Disabling Roaming in the Source Code:
--- readconf.c 30 Jul 2015 00:01:34 -0000 1.239
+++ readconf.c 13 Jan 2016 23:17:23 -0000
@@ -1648,7 +1648,7 @@ initialize_options(Options * options)
options->tun_remote = -1;
options->local_command = NULL;
options->permit_local_command = -1;
- options->use_roaming = -1;
+ options->use_roaming = 0;
options->visual_host_key = -1;
options->ip_qos_interactive = -1;
options->ip_qos_bulk = -1;
@@ -1819,8 +1819,7 @@ fill_default_options(Options * options)
options->tun_remote = SSH_TUNID_ANY;
if (options->permit_local_command == -1)
options->permit_local_command = 0;
- if (options->use_roaming == -1)
- options->use_roaming = 1;
+ options->use_roaming = 0;
if (options->visual_host_key == -1)
options->visual_host_key = 0;
if (options->ip_qos_interactive == -1)
--- ssh.c 30 Jul 2015 00:01:34 -0000 1.420
+++ ssh.c 13 Jan 2016 23:17:23 -0000
@@ -1882,9 +1882,6 @@ ssh_session2(void)
- if (options.use_roaming)
return client_loop(tty_flag, tty_flag ?
options.escape_char : SSH_ESCAPECHAR_NONE, id);
Corinna Vinschen Please, send mails regarding Cygwin to
Cygwin Project Co-Leader cygwin AT cygwin DOT com
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