summaryrefslogtreecommitdiff
path: root/debian/NEWS
diff options
context:
space:
mode:
Diffstat (limited to 'debian/NEWS')
-rw-r--r--debian/NEWS321
1 files changed, 321 insertions, 0 deletions
diff --git a/debian/NEWS b/debian/NEWS
new file mode 100644
index 000000000..1963c7919
--- /dev/null
+++ b/debian/NEWS
@@ -0,0 +1,321 @@
1openssh (1:8.2p1-1) unstable; urgency=medium
2
3 OpenSSH 8.2 includes a number of changes that may affect existing
4 configurations:
5
6 * ssh(1), sshd(8), ssh-keygen(1): This release removes the "ssh-rsa"
7 (RSA/SHA1) algorithm from those accepted for certificate signatures
8 (i.e. the client and server CASignatureAlgorithms option) and will use
9 the rsa-sha2-512 signature algorithm by default when the ssh-keygen(1)
10 CA signs new certificates.
11
12 Certificates are at special risk to SHA1 collision vulnerabilities as
13 an attacker has effectively unlimited time in which to craft a
14 collision that yields them a valid certificate, far more than the
15 relatively brief LoginGraceTime window that they have to forge a host
16 key signature.
17
18 The OpenSSH certificate format includes a CA-specified (typically
19 random) nonce value near the start of the certificate that should make
20 exploitation of chosen-prefix collisions in this context challenging,
21 as the attacker does not have full control over the prefix that
22 actually gets signed. Nonetheless, SHA1 is now a demonstrably broken
23 algorithm and futher improvements in attacks are highly likely.
24
25 OpenSSH releases prior to 7.2 do not support the newer RSA/SHA2
26 algorithms and will refuse to accept certificates signed by an OpenSSH
27 8.2+ CA using RSA keys unless the unsafe algorithm is explicitly
28 selected during signing ("ssh-keygen -t ssh-rsa"). Older
29 clients/servers may use another CA key type such as ssh-ed25519
30 (supported since OpenSSH 6.5) or one of the ecdsa-sha2-nistp256/384/521
31 types (supported since OpenSSH 5.7) instead if they cannot be upgraded.
32
33 * ssh(1), sshd(8): Remove diffie-hellman-group14-sha1 from the default
34 key exchange proposal for both the client and server.
35
36 * ssh-keygen(1): The command-line options related to the generation and
37 screening of safe prime numbers used by the
38 diffie-hellman-group-exchange-* key exchange algorithms have changed.
39 Most options have been folded under the -O flag.
40
41 * sshd(8): The sshd listener process title visible to ps(1) has changed
42 to include information about the number of connections that are
43 currently attempting authentication and the limits configured by
44 MaxStartups.
45
46 -- Colin Watson <cjwatson@debian.org> Fri, 21 Feb 2020 12:11:52 +0000
47
48openssh (1:8.1p1-1) unstable; urgency=medium
49
50 OpenSSH 8.1 includes a number of changes that may affect existing
51 configurations:
52
53 * ssh-keygen(1): when acting as a CA and signing certificates with an RSA
54 key, default to using the rsa-sha2-512 signature algorithm.
55 Certificates signed by RSA keys will therefore be incompatible with
56 OpenSSH versions prior to 7.2 unless the default is overridden (using
57 "ssh-keygen -t ssh-rsa -s ...").
58
59 -- Colin Watson <cjwatson@debian.org> Thu, 10 Oct 2019 10:23:19 +0100
60
61openssh (1:8.0p1-1) experimental; urgency=medium
62
63 OpenSSH 8.0 includes a number of changes that may affect existing
64 configurations:
65
66 * sshd(8): Remove support for obsolete "host/port" syntax.
67 Slash-separated host/port was added in 2001 as an alternative to
68 host:port syntax for the benefit of IPv6 users. These days there are
69 established standards for this like [::1]:22 and the slash syntax is
70 easily mistaken for CIDR notation, which OpenSSH supports for some
71 things. Remove the slash notation from ListenAddress and PermitOpen.
72
73 -- Colin Watson <cjwatson@debian.org> Sun, 09 Jun 2019 22:47:27 +0100
74
75openssh (1:7.9p1-1) unstable; urgency=medium
76
77 OpenSSH 7.9 includes a number of changes that may affect existing
78 configurations:
79
80 * ssh(1), sshd(8): the setting of the new CASignatureAlgorithms option
81 bans the use of DSA keys as certificate authorities.
82 * sshd(8): the authentication success/failure log message has changed
83 format slightly. It now includes the certificate fingerprint
84 (previously it included only key ID and CA key fingerprint).
85
86 -- Colin Watson <cjwatson@debian.org> Sun, 21 Oct 2018 10:39:24 +0100
87
88openssh (1:7.8p1-1) unstable; urgency=medium
89
90 OpenSSH 7.8 includes a number of changes that may affect existing
91 configurations:
92
93 * ssh-keygen(1): Write OpenSSH format private keys by default instead of
94 using OpenSSL's PEM format. The OpenSSH format, supported in OpenSSH
95 releases since 2014 and described in the PROTOCOL.key file in the
96 source distribution, offers substantially better protection against
97 offline password guessing and supports key comments in private keys.
98 If necessary, it is possible to write old PEM-style keys by adding "-m
99 PEM" to ssh-keygen's arguments when generating or updating a key.
100 * sshd(8): Remove internal support for S/Key multiple factor
101 authentication. S/Key may still be used via PAM or BSD auth.
102 * ssh(1): Remove vestigial support for running ssh(1) as setuid. This
103 used to be required for hostbased authentication and the (long gone)
104 rhosts-style authentication, but has not been necessary for a long
105 time. Attempting to execute ssh as a setuid binary, or with uid !=
106 effective uid will now yield a fatal error at runtime.
107 * sshd(8): The semantics of PubkeyAcceptedKeyTypes and the similar
108 HostbasedAcceptedKeyTypes options have changed. These now specify
109 signature algorithms that are accepted for their respective
110 authentication mechanism, where previously they specified accepted key
111 types. This distinction matters when using the RSA/SHA2 signature
112 algorithms "rsa-sha2-256", "rsa-sha2-512" and their certificate
113 counterparts. Configurations that override these options but omit
114 these algorithm names may cause unexpected authentication failures (no
115 action is required for configurations that accept the default for these
116 options).
117 * sshd(8): The precedence of session environment variables has changed.
118 ~/.ssh/environment and environment="..." options in authorized_keys
119 files can no longer override SSH_* variables set implicitly by sshd.
120 * ssh(1)/sshd(8): The default IPQoS used by ssh/sshd has changed. They
121 will now use DSCP AF21 for interactive traffic and CS1 for bulk. For a
122 detailed rationale, please see the commit message:
123 https://cvsweb.openbsd.org/src/usr.bin/ssh/readconf.c#rev1.284
124
125 -- Colin Watson <cjwatson@debian.org> Thu, 30 Aug 2018 15:35:27 +0100
126
127openssh (1:7.6p1-1) unstable; urgency=medium
128
129 OpenSSH 7.6 includes a number of changes that may affect existing
130 configurations:
131
132 * ssh(1): Delete SSH protocol version 1 support, associated configuration
133 options and documentation.
134 * ssh(1)/sshd(8): Remove support for the hmac-ripemd160 MAC.
135 * ssh(1)/sshd(8): Remove support for the arcfour, blowfish and CAST
136 ciphers.
137 * Refuse RSA keys <1024 bits in length and improve reporting for keys
138 that do not meet this requirement.
139 * ssh(1): Do not offer CBC ciphers by default.
140
141 -- Colin Watson <cjwatson@debian.org> Fri, 06 Oct 2017 12:36:48 +0100
142
143openssh (1:7.5p1-1) experimental; urgency=medium
144
145 OpenSSH 7.5 includes a number of changes that may affect existing
146 configurations:
147
148 * This release deprecates the sshd_config UsePrivilegeSeparation option,
149 thereby making privilege separation mandatory.
150
151 * The format of several log messages emitted by the packet code has
152 changed to include additional information about the user and their
153 authentication state. Software that monitors ssh/sshd logs may need to
154 account for these changes. For example:
155
156 Connection closed by user x 1.1.1.1 port 1234 [preauth]
157 Connection closed by authenticating user x 10.1.1.1 port 1234 [preauth]
158 Connection closed by invalid user x 1.1.1.1 port 1234 [preauth]
159
160 Affected messages include connection closure, timeout, remote
161 disconnection, negotiation failure and some other fatal messages
162 generated by the packet code.
163
164 -- Colin Watson <cjwatson@debian.org> Sun, 02 Apr 2017 02:58:01 +0100
165
166openssh (1:7.4p1-7) unstable; urgency=medium
167
168 This version restores the default for AuthorizedKeysFile to search both
169 ~/.ssh/authorized_keys and ~/.ssh/authorized_keys2, as was the case in
170 Debian configurations before 1:7.4p1-1. Upstream intends to phase out
171 searching ~/.ssh/authorized_keys2 by default, so you should ensure that
172 you are only using ~/.ssh/authorized_keys, at least for critical
173 administrative access; do not assume that the current default will remain
174 in place forever.
175
176 -- Colin Watson <cjwatson@debian.org> Sun, 05 Mar 2017 02:12:42 +0000
177
178openssh (1:7.4p1-1) unstable; urgency=medium
179
180 OpenSSH 7.4 includes a number of changes that may affect existing
181 configurations:
182
183 * ssh(1): Remove 3des-cbc from the client's default proposal. 64-bit
184 block ciphers are not safe in 2016 and we don't want to wait until
185 attacks like SWEET32 are extended to SSH. As 3des-cbc was the only
186 mandatory cipher in the SSH RFCs, this may cause problems connecting to
187 older devices using the default configuration, but it's highly likely
188 that such devices already need explicit configuration for key exchange
189 and hostkey algorithms already anyway.
190 * sshd(8): Remove support for pre-authentication compression. Doing
191 compression early in the protocol probably seemed reasonable in the
192 1990s, but today it's clearly a bad idea in terms of both cryptography
193 (cf. multiple compression oracle attacks in TLS) and attack surface.
194 Pre-auth compression support has been disabled by default for >10
195 years. Support remains in the client.
196 * ssh-agent will refuse to load PKCS#11 modules outside a whitelist of
197 trusted paths by default. The path whitelist may be specified at
198 run-time.
199 * sshd(8): When a forced-command appears in both a certificate and an
200 authorized keys/principals command= restriction, sshd will now refuse
201 to accept the certificate unless they are identical. The previous
202 (documented) behaviour of having the certificate forced-command
203 override the other could be a bit confusing and error-prone.
204 * sshd(8): Remove the UseLogin configuration directive and support for
205 having /bin/login manage login sessions.
206
207 The unprivileged sshd process that deals with pre-authentication network
208 traffic is now subject to additional sandboxing restrictions by default:
209 that is, the default sshd_config now sets UsePrivilegeSeparation to
210 "sandbox" rather than "yes". This has been the case upstream for a while,
211 but until now the Debian configuration diverged unnecessarily.
212
213 -- Colin Watson <cjwatson@debian.org> Tue, 27 Dec 2016 18:01:46 +0000
214
215openssh (1:7.2p1-1) unstable; urgency=medium
216
217 OpenSSH 7.2 disables a number of legacy cryptographic algorithms by
218 default in ssh:
219
220 * Several ciphers blowfish-cbc, cast128-cbc, all arcfour variants and the
221 rijndael-cbc aliases for AES.
222 * MD5-based and truncated HMAC algorithms.
223
224 These algorithms are already disabled by default in sshd.
225
226 -- Colin Watson <cjwatson@debian.org> Tue, 08 Mar 2016 11:47:20 +0000
227
228openssh (1:7.1p1-2) unstable; urgency=medium
229
230 OpenSSH 7.0 disables several pieces of weak, legacy, and/or unsafe
231 cryptography.
232
233 * Support for the legacy SSH version 1 protocol is disabled by default at
234 compile time. Note that this also means that the Cipher keyword in
235 ssh_config(5) is effectively no longer usable; use Ciphers instead for
236 protocol 2. The openssh-client-ssh1 package includes "ssh1", "scp1",
237 and "ssh-keygen1" binaries which you can use if you have no alternative
238 way to connect to an outdated SSH1-only server; please contact the
239 server administrator or system vendor in such cases and ask them to
240 upgrade.
241 * Support for the 1024-bit diffie-hellman-group1-sha1 key exchange is
242 disabled by default at run-time. It may be re-enabled using the
243 instructions at http://www.openssh.com/legacy.html
244 * Support for ssh-dss, ssh-dss-cert-* host and user keys is disabled by
245 default at run-time. These may be re-enabled using the instructions at
246 http://www.openssh.com/legacy.html
247 * Support for the legacy v00 cert format has been removed.
248
249 Future releases will retire more legacy cryptography, including:
250
251 * Refusing all RSA keys smaller than 1024 bits (the current minimum is
252 768 bits).
253 * Several ciphers will be disabled by default: blowfish-cbc, cast128-cbc,
254 all arcfour variants, and the rijndael-cbc aliases for AES.
255 * MD5-based HMAC algorithms will be disabled by default.
256
257 -- Colin Watson <cjwatson@debian.org> Tue, 08 Dec 2015 15:33:08 +0000
258
259openssh (1:6.9p1-1) unstable; urgency=medium
260
261 UseDNS now defaults to 'no'. Configurations that match against the client
262 host name (via sshd_config or authorized_keys) may need to re-enable it or
263 convert to matching against addresses.
264
265 -- Colin Watson <cjwatson@debian.org> Thu, 20 Aug 2015 10:38:58 +0100
266
267openssh (1:6.7p1-5) unstable; urgency=medium
268
269 openssh-server 1:6.7p1-4 changed the default setting of AcceptEnv to list
270 a number of specific LC_FOO variables rather than the wildcard LC_*. I
271 have since been persuaded that this was a bad idea and have reverted it,
272 but it is difficult to automatically undo the change to
273 /etc/ssh/sshd_config without compounding the problem (that of modifying
274 configuration that some users did not want to be modified) further. Most
275 users who upgraded via version 1:6.7p1-4 should restore the previous value
276 of "AcceptEnv LANG LC_*" in /etc/ssh/sshd_config.
277
278 -- Colin Watson <cjwatson@debian.org> Sun, 22 Mar 2015 23:09:32 +0000
279
280openssh (1:5.4p1-2) unstable; urgency=low
281
282 Smartcard support is now available using PKCS#11 tokens. If you were
283 previously using an unofficial build of Debian's OpenSSH package with
284 OpenSC-based smartcard support added, then note that commands like
285 'ssh-add -s 0' will no longer work; you need to use 'ssh-add -s
286 /usr/lib/opensc-pkcs11.so' instead.
287
288 -- Colin Watson <cjwatson@debian.org> Sat, 10 Apr 2010 01:08:59 +0100
289
290openssh (1:3.8.1p1-9) experimental; urgency=low
291
292 The ssh package has been split into openssh-client and openssh-server. If
293 you had previously requested that the sshd server should not be run, then
294 that request will still be honoured. However, the recommended approach is
295 now to remove the openssh-server package if you do not want to run sshd.
296 You can remove the old /etc/ssh/sshd_not_to_be_run marker file after doing
297 that.
298
299 -- Colin Watson <cjwatson@debian.org> Mon, 2 Aug 2004 20:48:54 +0100
300
301openssh (1:3.5p1-1) unstable; urgency=low
302
303 This version of OpenSSH disables the environment option for public keys by
304 default, in order to avoid certain attacks (for example, LD_PRELOAD). If
305 you are using this option in an authorized_keys file, beware that the keys
306 in question will no longer work until the option is removed.
307
308 To re-enable this option, set "PermitUserEnvironment yes" in
309 /etc/ssh/sshd_config after the upgrade is complete, taking note of the
310 warning in the sshd_config(5) manual page.
311
312 -- Colin Watson <cjwatson@debian.org> Sat, 26 Oct 2002 19:41:51 +0100
313
314openssh (1:3.0.1p1-1) unstable; urgency=high
315
316 As of version 3, OpenSSH no longer uses separate files for ssh1 and ssh2
317 keys. This means the authorized_keys2 and known_hosts2 files are no longer
318 needed. They will still be read in order to maintain backward
319 compatibility.
320
321 -- Matthew Vernon <matthew@debian.org> Thu, 28 Nov 2001 17:43:01 +0000