similar to: key rotation on ssh servers

Hi, You will be aware of https://weakdh.org/ by now, I presume; the take-home seems to be that 1024-bit DH primes might well be too weak. I'm wondering what (if anything!) you propose to do about this issue, and what Debian might do for our users? openssh already prefers ECDH, which must reduce the impact somewhat, although the main Windows client (PuTTY) doesn't support ECDH yet. But

https://bugzilla.mindrot.org/show_bug.cgi?id=3219 Bug ID: 3219 Summary: Can't connect to a server that is using several host keys of the same type Product: Portable OpenSSH Version: 8.4p1 Hardware: amd64 OS: Linux Status: NEW Severity: normal Priority: P5

Hi, Is there any way to store HostKey in hardware (and delegate the related processing)? I have been using Roumen Petrov's x509 patch for clients, which works via an OpenSSL engine, but it does not seem to support server HostKey: http://roumenpetrov.info/pipermail/ssh_x509_roumenpetrov.info/2012q4/000019.html For PKCS#11, I have found an email on this list from a year back suggesting this

Hi, I discovered when using my fuse fs for connecting to a remote host using sftp that the new server version 7.4 sends a greeter which is not according the format desribed in https://tools.ietf.org/html/rfc4253#section-4 There is written that the greeter "MUST be terminated by a single Carriage Return (CR) and a single Line Feed (LF) character (ASCII 13 and 10, respectively)." Now

Am I correct in assuming that the user and host public/private keys used in openSSH are only used for authentication (is the remote server known to be X, is this Harry trying to login), and have no role in the encryption? I was under the assumption that each connection used a newly generated key (using DH for key exchange) so each session was unique. (I believe this because the transport layer

Hi all, I have recently only discovered that openssh prints lines to stderr separated by CLRF pairs, and am trying to understand where this behavior comes from. This behavior can be seen here: --snip-- $ ssh u at u 2>&1 | sed -n l ssh: Could not resolve hostname u: Name or service not known\r$ --snip-- I have seen section 11.3 from rfc4253, but am unsure whether that is the origin of

Hi, About a year and a half ago I brought up the topic of encrypted hostkeys and posted a patch (http://marc.info/?l=openssh-unix-dev&m=132774431906364&w=2), and while the general reaction seemed receptive to the idea, a few problems were pointed out with the implementation (UI issues, ssh-keysign breakage). I've finally had some spare time in which to get back to this, and I've

This message is a few years old so I cannot reply to the original, but it is still of current research interest. > So one of my coworkers is doing a little research on SSH usage in the > wild using netflow data. One of the things he's trying to do is > determine a way to differentiate between data transfers and interactive > sessions. We thought of a couple of ways but we wanted

The full SSH_MSG_CHANNEL_DATA packet looks like this: uint32 packet length byte SSH_MSG_CHANNEL_DATA uint32 recipient channel uint32 nr data bytes byte[] data OpenSSH_6.1p1 considers that the 'maximum packet size' from SSH_MSG_CHANNEL_OPEN or SSH_MSG_CHANNEL_OPEN_CONFIRMATION impacts only the 'byte[] data' field and not the entire message (headers included).

Hi, according to RFC 4253 https://www.rfc-editor.org/rfc/rfc4253#section-7.1 for the selection of algorithms (ciphers, KEX, MAC etc.), the leftmost matching client algorithm is picked. While this is fine in most cases, there are cases where it is not desirable, for example: 1) for compatibility with a single old client you enable an old cipher, say aes128-cbc, server side. A modern client

Compiled OK, and operating nicely on CentOS 6.6, both 32/64 bit. Really appreciate the UpdateHostkeys feature! One issue I noticed, the screen output gets garbled if the user has been "asked" to "Accept" the new hostkeys. Looks like the screen output is missing the CR's, and only LF's get presented. [root at be2 .ssh]# ssh be1 ls -l Warning: Permanently added

While compiling openssl with option `no-des', it caused the openssh build failure ... cipher.c:85:41: error: 'EVP_des_ede3_cbc' undeclared here (not in a function); ... Signed-off-by: Hongxu Jia <hongxu.jia at windriver.com> --- cipher.c | 2 ++ configure.ac | 20 ++++++++++++++++++++ 2 files changed, 22 insertions(+) diff --git a/cipher.c b/cipher.c index

This (very quick) patch allows you to connect with the commercial ssh.com windows client and use x509 certs for hostkeys. You have to import your CA cert (ca.crt) in the windows client and certify your hostkey: $ cat << 'EOF' > x509v3.cnf CERTPATHLEN = 1 CERTUSAGE = digitalSignature,keyCertSign CERTIP = 0.0.0.0 [x509v3_CA]

Hi, OpenSSH plans to remove support for DSA keys in the near future. This message describes our rationale, process and proposed timeline. Rationale --------- DSA, as specified in the SSHv2 protocol, is inherently weak - being limited to a 160 bit private key and use of the SHA1 digest. Its estimated security level is <=80 bits symmetric equivalent[1][2]. OpenSSH has disabled DSA keys by

Hi, OpenSSH plans to remove support for DSA keys in the near future. This message describes our rationale, process and proposed timeline. Rationale --------- DSA, as specified in the SSHv2 protocol, is inherently weak - being limited to a 160 bit private key and use of the SHA1 digest. Its estimated security level is <=80 bits symmetric equivalent[1][2]. OpenSSH has disabled DSA keys by

Hello, OpenSSH-wizards. In our company, we have looked into SSH-HostKey-signing in order to realize automated access without the need to accept the server's hostkey, manually. I got it to work with the HostCertificate-directive inside the sshd_config. Now, I was wondering whether it is possible to have multiple signatures, so I can, for example, sign the hostkey once with a

Am 02.11.2013 um 11:38 schrieb Aris Adamantiadis <aris at 0xbadc0de.be>: > RFC4251 describes mpint to be multi-size and with positive values having > MSB clear, so it's clearly incompatible with raw string. > > Since you both agreed on the curve25519 implementation to use, I'll work > today on Markus' patch to make the changes Damien wanted. What do you want to

https://bugzilla.mindrot.org/show_bug.cgi?id=3155 Bug ID: 3155 Summary: openssh support hostkey encrypt Product: Portable OpenSSH Version: 8.2p1 Hardware: ARM64 OS: Linux Status: NEW Severity: security Priority: P5 Component: ssh-keygen Assignee: unassigned-bugs at mindrot.org

https://bugzilla.mindrot.org/show_bug.cgi?id=1657 Summary: Server Authentication when both RSA and DSA are enabled (on the server) Product: Portable OpenSSH Version: 5.2p1 Platform: All OS/Version: All Status: NEW Severity: trivial Priority: P2 Component: ssh AssignedTo:

When connecting to a host for which there's no known hostkey, check if the relevant key has been accepted for other hostnames. This is useful when connecting to a host with a dymamic IP address or multiple names. --- auth.c | 4 ++-- hostfile.c | 42 ++++++++++++++++++++++++++++-------------- hostfile.h | 8 ++++++-- sshconnect.c | 39 +++++++++++++++++++++++++++++++++------