the support in the rest of the source tree.
X11 sets could use some cleaning up perhaps (just deletion, as
we've never really marked the old X11R6 as obsolete for native
xorg using platforms so far either.)
*) Alternate chains certificate forgery
During certificate verfification, OpenSSL will attempt to find an
alternative certificate chain if the first attempt to build such a chain
fails. An error in the implementation of this logic can mean that an
attacker could cause certain checks on untrusted certificates to be
bypassed, such as the CA flag, enabling them to use a valid leaf
certificate to act as a CA and "issue" an invalid certificate.
This issue was reported to OpenSSL by Adam Langley/David Benjamin
(Google/BoringSSL).
[Matt Caswell]
=========================
This is primarily a bugfix release.
Security
--------
* ssh(1): when forwarding X11 connections with ForwardX11Trusted=no,
connections made after ForwardX11Timeout expired could be permitted
and no longer subject to XSECURITY restrictions because of an
ineffective timeout check in ssh(1) coupled with "fail open"
behaviour in the X11 server when clients attempted connections with
expired credentials. This problem was reported by Jann Horn.
* ssh-agent(1): fix weakness of agent locking (ssh-add -x) to
password guessing by implementing an increasing failure delay,
storing a salted hash of the password rather than the password
itself and using a timing-safe comparison function for verifying
unlock attempts. This problem was reported by Ryan Castellucci.
New Features
------------
* ssh(1), sshd(8): promote chacha20-poly1305@openssh.com to be the
default cipher
* sshd(8): support admin-specified arguments to AuthorizedKeysCommand;
bz#2081
* sshd(8): add AuthorizedPrincipalsCommand that allows retrieving
authorized principals information from a subprocess rather than
a file.
* ssh(1), ssh-add(1): support PKCS#11 devices with external PIN
entry devices bz#2240
* sshd(8): allow GSSAPI host credential check to be relaxed for
multihomed hosts via GSSAPIStrictAcceptorCheck option; bz#928
* ssh-keygen(1): support "ssh-keygen -lF hostname" to search
known_hosts and print key hashes rather than full keys.
* ssh-agent(1): add -D flag to leave ssh-agent in foreground without
enabling debug mode; bz#2381
Bugfixes
--------
* ssh(1), sshd(8): deprecate legacy SSH2_MSG_KEX_DH_GEX_REQUEST_OLD
message and do not try to use it against some 3rd-party SSH
implementations that use it (older PuTTY, WinSCP).
* Many fixes for problems caused by compile-time deactivation of
SSH1 support (including bz#2369)
* ssh(1), sshd(8): cap DH-GEX group size at 4Kbits for Cisco
implementations as some would fail when attempting to use group
sizes >4K; bz#2209
* ssh(1): fix out-of-bound read in EscapeChar configuration option
parsing; bz#2396
* sshd(8): fix application of PermitTunnel, LoginGraceTime,
AuthenticationMethods and StreamLocalBindMask options in Match
blocks
* ssh(1), sshd(8): improve disconnection message on TCP reset;
bz#2257
* ssh(1): remove failed remote forwards established by muliplexing
from the list of active forwards; bz#2363
* sshd(8): make parsing of authorized_keys "environment=" options
independent of PermitUserEnv being enabled; bz#2329
* sshd(8): fix post-auth crash with permitopen=none; bz#2355
* ssh(1), ssh-add(1), ssh-keygen(1): allow new-format private keys
to be encrypted with AEAD ciphers; bz#2366
* ssh(1): allow ListenAddress, Port and AddressFamily configuration
options to appear in any order; bz#86
* sshd(8): check for and reject missing arguments for VersionAddendum
and ForceCommand; bz#2281
* ssh(1), sshd(8): don't treat unknown certificate extensions as
fatal; bz#2387
* ssh-keygen(1): make stdout and stderr output consistent; bz#2325
* ssh(1): mention missing DISPLAY environment in debug log when X11
forwarding requested; bz#1682
* sshd(8): correctly record login when UseLogin is set; bz#378
* sshd(8): Add some missing options to sshd -T output and fix output
of VersionAddendum and HostCertificate. bz#2346
* Document and improve consistency of options that accept a "none"
argument" TrustedUserCAKeys, RevokedKeys (bz#2382),
AuthorizedPrincipalsFile (bz#2288)
* ssh(1): include remote username in debug output; bz#2368
* sshd(8): avoid compatibility problem with some versions of Tera
Term, which would crash when they received the hostkeys notification
message (hostkeys-00@openssh.com)
* sshd(8): mention ssh-keygen -E as useful when comparing legacy MD5
host key fingerprints; bz#2332
* ssh(1): clarify pseudo-terminal request behaviour and use make
manual language consistent; bz#1716
* ssh(1): document that the TERM environment variable is not subject
to SendEnv and AcceptEnv; bz#2386
*) Malformed ECParameters causes infinite loop
When processing an ECParameters structure OpenSSL enters an infinite loop
if the curve specified is over a specially malformed binary polynomial
field.
This can be used to perform denial of service against any
system which processes public keys, certificate requests or
certificates. This includes TLS clients and TLS servers with
client authentication enabled.
This issue was reported to OpenSSL by Joseph Barr-Pixton.
(CVE-2015-1788)
[Andy Polyakov]
*) Exploitable out-of-bounds read in X509_cmp_time
X509_cmp_time does not properly check the length of the ASN1_TIME
string and can read a few bytes out of bounds. In addition,
X509_cmp_time accepts an arbitrary number of fractional seconds in the
time string.
An attacker can use this to craft malformed certificates and CRLs of
various sizes and potentially cause a segmentation fault, resulting in
a DoS on applications that verify certificates or CRLs. TLS clients
that verify CRLs are affected. TLS clients and servers with client
authentication enabled may be affected if they use custom verification
callbacks.
This issue was reported to OpenSSL by Robert Swiecki (Google), and
independently by Hanno Böck.
(CVE-2015-1789)
[Emilia Käsper]
*) PKCS7 crash with missing EnvelopedContent
The PKCS#7 parsing code does not handle missing inner EncryptedContent
correctly. An attacker can craft malformed ASN.1-encoded PKCS#7 blobs
with missing content and trigger a NULL pointer dereference on parsing.
Applications that decrypt PKCS#7 data or otherwise parse PKCS#7
structures from untrusted sources are affected. OpenSSL clients and
servers are not affected.
This issue was reported to OpenSSL by Michal Zalewski (Google).
(CVE-2015-1790)
[Emilia Käsper]
*) CMS verify infinite loop with unknown hash function
When verifying a signedData message the CMS code can enter an infinite loop
if presented with an unknown hash function OID. This can be used to perform
denial of service against any system which verifies signedData messages using
the CMS code.
This issue was reported to OpenSSL by Johannes Bauer.
(CVE-2015-1792)
[Stephen Henson]
*) Race condition handling NewSessionTicket
If a NewSessionTicket is received by a multi-threaded client when attempting to
reuse a previous ticket then a race condition can occur potentially leading to
a double free of the ticket data.
(CVE-2015-1791)
[Matt Caswell]
*) Reject DH handshakes with parameters shorter than 768 bits.
[Kurt Roeckx and Emilia Kasper]
=========================
This is a major release, containing a number of new features as
well as a large internal re-factoring.
Potentially-incompatible changes
--------------------------------
* sshd(8): UseDNS now defaults to 'no'. Configurations that match
against the client host name (via sshd_config or authorized_keys)
may need to re-enable it or convert to matching against addresses.
New Features
------------
* Much of OpenSSH's internal code has been re-factored to be more
library-like. These changes are mostly not user-visible, but
have greatly improved OpenSSH's testability and internal layout.
* Add FingerprintHash option to ssh(1) and sshd(8), and equivalent
command-line flags to the other tools to control algorithm used
for key fingerprints. The default changes from MD5 to SHA256 and
format from hex to base64.
Fingerprints now have the hash algorithm prepended. An example of
the new format: SHA256:mVPwvezndPv/ARoIadVY98vAC0g+P/5633yTC4d/wXE
Please note that visual host keys will also be different.
* ssh(1), sshd(8): Experimental host key rotation support. Add a
protocol extension for a server to inform a client of all its
available host keys after authentication has completed. The client
may record the keys in known_hosts, allowing it to upgrade to better
host key algorithms and a server to gracefully rotate its keys.
The client side of this is controlled by a UpdateHostkeys config
option (default off).
* ssh(1): Add a ssh_config HostbasedKeyType option to control which
host public key types are tried during host-based authentication.
* ssh(1), sshd(8): fix connection-killing host key mismatch errors
when sshd offers multiple ECDSA keys of different lengths.
* ssh(1): when host name canonicalisation is enabled, try to
parse host names as addresses before looking them up for
canonicalisation. fixes bz#2074 and avoiding needless DNS
lookups in some cases.
* ssh-keygen(1), sshd(8): Key Revocation Lists (KRLs) no longer
require OpenSSH to be compiled with OpenSSL support.
* ssh(1), ssh-keysign(8): Make ed25519 keys work for host based
authentication.
* sshd(8): SSH protocol v.1 workaround for the Meyer, et al,
Bleichenbacher Side Channel Attack. Fake up a bignum key before
RSA decryption.
* sshd(8): Remember which public keys have been used for
authentication and refuse to accept previously-used keys.
This allows AuthenticationMethods=publickey,publickey to require
that users authenticate using two _different_ public keys.
* sshd(8): add sshd_config HostbasedAcceptedKeyTypes and
PubkeyAcceptedKeyTypes options to allow sshd to control what
public key types will be accepted. Currently defaults to all.
* sshd(8): Don't count partial authentication success as a failure
against MaxAuthTries.
* ssh(1): Add RevokedHostKeys option for the client to allow
text-file or KRL-based revocation of host keys.
* ssh-keygen(1), sshd(8): Permit KRLs that revoke certificates by
serial number or key ID without scoping to a particular CA.
* ssh(1): Add a "Match canonical" criteria that allows ssh_config
Match blocks to trigger only in the second config pass.
* ssh(1): Add a -G option to ssh that causes it to parse its
configuration and dump the result to stdout, similar to "sshd -T".
* ssh(1): Allow Match criteria to be negated. E.g. "Match !host".
* The regression test suite has been extended to cover more OpenSSH
features. The unit tests have been expanded and now cover key
exchange.
Bugfixes
* ssh-keyscan(1): ssh-keyscan has been made much more robust again
servers that hang or violate the SSH protocol.
* ssh(1), ssh-keygen(1): Fix regression bz#2306: Key path names were
being lost as comment fields.
* ssh(1): Allow ssh_config Port options set in the second config
parse phase to be applied (they were being ignored). bz#2286
* ssh(1): Tweak config re-parsing with host canonicalisation - make
the second pass through the config files always run when host name
canonicalisation is enabled (and not whenever the host name
changes) bz#2267
* ssh(1): Fix passing of wildcard forward bind addresses when
connection multiplexing is in use; bz#2324;
* ssh-keygen(1): Fix broken private key conversion from non-OpenSSH
formats; bz#2345.
* ssh-keygen(1): Fix KRL generation bug when multiple CAs are in
use.
* Various fixes to manual pages: bz#2288, bz#2316, bz#2273
Portable OpenSSH
* Support --without-openssl at configure time
Disables and removes dependency on OpenSSL. Many features,
including SSH protocol 1 are not supported and the set of crypto
options is greatly restricted. This will only work on systems
with native arc4random or /dev/urandom.
Considered highly experimental for now.
* Support --without-ssh1 option at configure time
Allows disabling support for SSH protocol 1.
* sshd(8): Fix compilation on systems with IPv6 support in utmpx; bz#2296
* Allow custom service name for sshd on Cygwin. Permits the use of
multiple sshd running with different service names.
Checksums:
==========
- SHA1 (openssh-6.8.tar.gz) = 99903c6ca76e0a2c044711017f81127e12459d37
- SHA256 (openssh-6.8.tar.gz) = N1uzVarFbrm2CzAwuDu3sRoszmqpK+5phAChP/QNyuw=
- SHA1 (openssh-6.8p1.tar.gz) = cdbc51e46a902b30d263b05fdc71340920e91c92
- SHA256 (openssh-6.8p1.tar.gz) = P/ZM5z7hJEgLW/dnuYMNfTwDu8tqvnFrePAZLDfOFg4=
Please note that the PGP key used to sign releases was recently rotated.
The new key has been signed by the old key to provide continuity. It is
available from the mirror sites as RELEASE_KEY.asc.
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.
The vulnerabilities listed below were previously fixed by patches
supplied by the OpenSSL project.
Thus, this import is not about vulnerabilities, but about the change
in source style OpenSSL applied before 1.0.1m (as well as small fixes
not listed in the changelog that make us have a 'proper' 1.0.1m).
Upstream Changelog:
Changes between 1.0.1l and 1.0.1m [19 Mar 2015]
*) Segmentation fault in ASN1_TYPE_cmp fix
The function ASN1_TYPE_cmp will crash with an invalid read if an attempt is
made to compare ASN.1 boolean types. Since ASN1_TYPE_cmp is used to check
certificate signature algorithm consistency this can be used to crash any
certificate verification operation and exploited in a DoS attack. Any
application which performs certificate verification is vulnerable including
OpenSSL clients and servers which enable client authentication.
(CVE-2015-0286)
[Stephen Henson]
*) ASN.1 structure reuse memory corruption fix
Reusing a structure in ASN.1 parsing may allow an attacker to cause
memory corruption via an invalid write. Such reuse is and has been
strongly discouraged and is believed to be rare.
Applications that parse structures containing CHOICE or ANY DEFINED BY
components may be affected. Certificate parsing (d2i_X509 and related
functions) are however not affected. OpenSSL clients and servers are
not affected.
(CVE-2015-0287)
[Stephen Henson]
*) PKCS7 NULL pointer dereferences fix
The PKCS#7 parsing code does not handle missing outer ContentInfo
correctly. An attacker can craft malformed ASN.1-encoded PKCS#7 blobs with
missing content and trigger a NULL pointer dereference on parsing.
Applications that verify PKCS#7 signatures, decrypt PKCS#7 data or
otherwise parse PKCS#7 structures from untrusted sources are
affected. OpenSSL clients and servers are not affected.
This issue was reported to OpenSSL by Michal Zalewski (Google).
(CVE-2015-0289)
[Emilia Käsper]
*) DoS via reachable assert in SSLv2 servers fix
A malicious client can trigger an OPENSSL_assert (i.e., an abort) in
servers that both support SSLv2 and enable export cipher suites by sending
a specially crafted SSLv2 CLIENT-MASTER-KEY message.
This issue was discovered by Sean Burford (Google) and Emilia Käsper
(OpenSSL development team).
(CVE-2015-0293)
[Emilia Käsper]
*) Use After Free following d2i_ECPrivatekey error fix
A malformed EC private key file consumed via the d2i_ECPrivateKey function
could cause a use after free condition. This, in turn, could cause a double
free in several private key parsing functions (such as d2i_PrivateKey
or EVP_PKCS82PKEY) and could lead to a DoS attack or memory corruption
for applications that receive EC private keys from untrusted
sources. This scenario is considered rare.
This issue was discovered by the BoringSSL project and fixed in their
commit 517073cd4b.
(CVE-2015-0209)
[Matt Caswell]
*) X509_to_X509_REQ NULL pointer deref fix
The function X509_to_X509_REQ will crash with a NULL pointer dereference if
the certificate key is invalid. This function is rarely used in practice.
This issue was discovered by Brian Carpenter.
(CVE-2015-0288)
[Stephen Henson]
*) Removed the export ciphers from the DEFAULT ciphers
[Kurt Roeckx]
Changes between 1.0.1k and 1.0.1l [15 Jan 2015]
*) Build fixes for the Windows and OpenVMS platforms
[Matt Caswell and Richard Levitte]
lines are changed into either #define SOMETHING or #undef SOMETHING,
but in our in-tree build it is installed verbatim - so comment out all
#undef parts, to allow our makefile fragments to freely -DSOMETHING
and not have it silently canceld here.
mrg