Articles from security category

New Features

• SFTP and SCP file transfer services can now listen on IPv6 addresses and accept connections from IPv6 clients. [server-side][sftp][scp] [#1924]
• The HTTP and HTTPS service now accepts creating new folders with the HTTP PUT and WebDAV MKCOL methods. [server-side][http][https] [#4828-1]
• The HTTP and HTTPS service now accepts deleting folders and files with the HTTP DELETE method. [server-side][http][https] [#4828-2]
• The HTTP and HTTPS service now accepts file uploads using the HTTP PUT method. [server-side][http][https] [#4828]

Defect fixes

• FTP and FTPS client side transfer can now transfer files larger than a few bytes from a remote FTP/FTPS server and to the local filesystem. This issue was introduced in SFTPPlus version 3.20.0. This defect was not affecting uploading / pushing files to a remote FTP/FTPS server. [client-side][ftp][ftps] [#4754]
• The Developer Documentation for the HTTP authentication method was updated to make it clear the expected repose codes for the authentication server. [server-side] [#4758]
• The JavaScript UI for the HTTP and HTTPS file transfer services no longer limit the file size to 256MB. This defect was introduced in 3.31.0. [server-side][http][https] [#4815]

Deprecations and Removals

• The default secure ssl_cipher_list configuration was updated to HIGH:!PSK:!RSP:!eNULL:!aNULL:!RC4:!MD5:!DES:!3DES:!aDH:!kDH:!DSS. The previous value was ALL:!RC4:!DES:!3DES:!MD5:!EXP. In this way, when updating the OpenSSL library you will automatically get an update in the list of secure ciphers, without the need to update SFTPPlus. [security][ftps][https][client-side][server-side] [#4748]
• The event (ID 40025) that was emitted when an unknown error was generated by the HTTP service during a JSON API request was removed. It has been replaced with event ID 40003. [server-side][http][https] [#4828]

You can check the full release notes here.

Exclude DES and Triple-DES from the SSL Cipher List

SFTPPlus relies on OS crypto for the SSL/TLS portion. There is no need to run this configuration if your operating system has already deprecated the use of DES/3DES.

To check if your OpenSSL has DES and 3DES ciphers enabled, check the output of openssl ciphers -v 'DES:3DES'

If DES/3DES are still available in OpenSSL, disable them for SFTPPlus by ensuring that the ssl_cipher_list configuration for the service has the value :!DES:!3DES: added in the list. This will exclude the use of DES and Triple DES as indicated by the ! mark.

For more details about this configuration, please refer to the ssl cipher list configuration option here.

Exclude DES and Triple-DES from the SSH Cipher List

In the ssh_cipher_list configuration for the service, add the value :!DES:!3DES: to exclude the use of DES and Triple DES. There is no need to run this configuration if your operating system has already deprecated the use of DES/3DES.

More details about this configuration for the ssh cipher list here.

Only use TLS 1.2 (for services utilizing TLS/SSL)

In the ssl_allowed_methods option for the associate service, add the value tlsv1.2 to use TLS v1.2.

Ensure that tlsv1.2 is the only value in ssl_allowed_methods so that this component will use TLS v1.2 during the secure communication handshake.

DES ciphers are used in TLS 1.0 and TLS 1.1, but they are not available in TLS 1.2 as noted in RFC 5469.

In the event that you still require communication with services still utilizing TLS 1.1 and/or TLS 1.0, you may add tlsv1.1 and/or tlsv1.0 providing that the DES and Triple-DES ciphers are excluded in the first instance.

More details about this configuration are available in our documentation here.

Confirming the SFTP configurations using openssl s_client

You can use openssl s-client, a diagnostic tool.

Connect via openssl s_client -cipher 3DES -connect site:port to check that 3DES is disabled.

To check the TLS version, the output will also reveal which TLS version is being used:

SSL-Session:
    Protocol  : TLSv1.2
    Cipher    : 0000
    Session-ID:
    Session-ID-ctx:
    Master-Key:
    Key-Arg   : None
    PSK identity: None
    PSK identity hint: None
    SRP username: None
    Start Time: 1519733544
    Timeout   : 300 (sec)
    Verify return code: 0 (ok)

Confirming the FTPS configurations using curl

If you wish to use curl instead, there are two tests that you can run once these options are saved in your development lab.

Run curl with the excluded ciphers DES-CBC3-SHA and check that you cannot complete the operation.

curl -v --ftp-ssl -k ftp://user@domain:port --ciphers DES-CBC3-SHA

Run curl with the allowed TLS version and check that you are able to complete the operation.

curl -v --ftp-ssl -k ftp://user@domain:port --tlsv1.2

Using --tlsv1.0 should fail the operation.

Confirming the configuration from the log

SFTPPlus configurations can also be confirmed via the log. For this issue, it should be done more as a supplementary step rather than as a sole point of confirmation of your configuration changes.

From the client-shell:

| SFTPPlus (3.30.0) file transfer client shell
| > connect
| 20140 2018-02-04 10:23:03 uuid Process 0.0.0.0:0 Connecting resource "ftpse".
| 10102 2018-02-04 10:23:03 uuid user localhost:10021 Location ftpse connected
  to the FTP server.
| 10106 2018-02-04 10:23:03 uuid user localhost:10021 Connection to FTP/FTPS
  was authenticated for location ftpse. Protected using TLSv1.2
  ECDHE-RSA-AES256-GCM-SHA384.
  Server certificate: (4) C=UK/O=ACME/CN=myserver.

From the server-side log:

| 10059 2019-06-18 09:42:36 ftp-1 johnd 127.0.0.1:48218
  User successfully logged on "/users/John_D" as "/".
  Command protected using TLSv1.2 ECDHE-RSA-CHACHA20-POLY1305.
  Client certificate: (2) C=GB/O=ACME/CN=myclient

The logs above indicate that TLSv1.2 was used alongside the list of ciphers ECDHE-RSA-AES256-GCM-SHA384. Please note that just because TLSv1.2 is used, it does not indicate that other TLS versions are disabled.

Security advisory about the Meltdown and Spectre are vulnerabilities

Meltdown and Spectre are vulnerabilities based on CPU design flaws which require the attacker to be able to execute application code which is created to exploit these vulnerabilities.

SFTPPlus secure file transfers does not allow any arbitrary application code execution. It will only read and write data without executing it. This is standard behaviour for doing file transfers over FTPS or HTTPS.

The SSH implementation of SFTPPlus is only allowed for the SFTP and SCP protocols. Shell access or any other SSH execution is denied. The SCP protocol is implemented using an embedded SCP protocol and no external scp application is called.

For the purpose of managed file transfers, SFTPPlus allows the execution of pre-configured application code with the pre and post transfer hooks. As long as the SFTPPlus is configured with trusted applications, this does not constitute an attack vector.

If you are running SFTPPlus Itanium architectures, for example with HPUX, you are not affected by these vulnerabilities, no mater what other software is in used on those systems.

SPARC architecture (example with Solaris 10) and POWER (example with AIX 7.1) are affected by the Spectre, while not being affected by Meltdown.

The embedded devices based on ARM64 CPUs are also affected by Spectre.

Administrators using the SFTPPlus MFT Client with pre and post transfer hooks should review the configuration and make sure that the hooks will trigger calls to trusted applications.

This article was written as of SFTPPlus version 3.31.0.

New Features

• The option to enforce unique names for uploaded files is now available for the HTTP and HTTPS file transfer services. [server-side] [#4465]
• A SOCKS version 5 (SOCKS5) proxy without authentication can now be used to connect to remote SFTP and SCP servers. [client-side][sftp][scp] [#4546]
• A new event handler option is added in order to send filtered events to standard output. This can be used when running SFTPPlus in Docker or with other process supervisors. [#4645]
• The option to enforce unique names for uploaded files is now available for the FTP, Implicit FTPS and Explicit FTPS protocols. [server-side] [#4650]
• The file-dispatcher event handler can now be configured to automatically create destination folders. [#4652]
• The close event description for SFTP and SCP client-side and server-side connection now contains the encryption used to protect connection. [client-side][server-side][sftp][scp] [#4668]
• The HTTP and HTTPS file transfer services now allow uploading multiple files and adding files via drag and drop. [server-side][http][https] [#4673]
• Support for Red Hat Enterprise Linux versions 7.0 to 7.3 with OpenSSL 1.0.1 was readded alongside support for RHEL 7.4 and newer using OpenSSL 1.0.2. [#4691]
• A new secure configuration value is available for the ssl_cipher_list and ssh_cipher_list as part of the FTPS, SFTP, SCP, and HTTPS file transfer services. [security][client-side][server-side] [#4727]

Defect fixes

• The transfer for SFTP and SCP locations is no longer interrupted when the remote server is requesting a SSH re-key exchange. This was affecting client-side transfers of files bigger than 1GB, as this is the point where some servers are re-keying. This is when either side forces the other to run the key-exchange phase which changes the encryption and integrity keys for the session. [client-side] [#4302]
• It is now possible to stop the client shell at any time by pressing the Ctrl+C key combination. In previous versions this was not available while an operation was in progress. [#4626]
• The AIX 7.1 build of SFTPPlus was updated to work with older OpenSSL versions. Previous versions of SFTPPlus (from 3.27.0 to 3.30.0) on AIX 7.1 required OpenSSL 1.0.2k or newer. [#4696]
• SFTP and SCP client and server side can now handle key exchange process even for peers which advertise their SSH version string with trailing spaces. This can happen for Bitvise SSHD Server when configured to omit its version. [client-side][server-side][sftp][scp] [#4718]
• The documentation for expression matching was updated to explain that regular expression matching is done as a search operation. For an exact match, use the start and end regex anchors. [#4724]

Deprecations and Removals

• Events with ID 40015 and 40016 were replaced by already existing event with ID 40022. Event 40022 is now the only one emitted when there are errors during an upload operation. [server-side][http] [#4465]
• The default configuration for SFTP, SCP, FTPS, and HTTPS connections was updated to exclude the 3DES cipher in order to prevent SWEET32 attacks. To not break backward compatibility for existing installations, this change affects only new installations. Existing installations will need to be manually updated to exclude the 3DES based ciphers. [#4727]

You can check the full release notes.

Why read this guide

In order to implement a secure managed file transfer system, you will need a good understanding of the supported services and protocols involved.

This article provides an overview of the supported protocols, including the advantages and disadvantages of these protocols as well as situations for the use of these services.

The first part focuses on protocols that we recommend you reconsider in using and the rest of the article is followed by services that we do recommend.

Protocols to reconsider when securing data and file transfers

The following, FTP and HTTP, are covered below as they both pose two services that offer the least advantage in terms of securing data and file transfers.

Protocols to consider when securing data and file transfers

The following are protocols and services that we do recommend for securing data and file transfers. This is not an exhaustive list.

SFTPPlus MFT bewerten

Die in diesem Artikel aufgeführten Funktionen sind nur einige ausgewählte Funktionen aus vielen heute verfügbaren Integrations- und Konfigurationsoptionen. Sprechen Sie mit dem Support-Team über Ihre Anforderungen an die Datenaustausch-Software.

SFTPPlus MFT Server unterstützt FTP, Explizites FTPS, Implizites FTPS, SFTP, SCP, HTTP und HTTPS.

SFTPPlus MFT ist als On-Premise-Lösung erhältlich, die auf Windows, Linux und macOS unterstützt wird.

Es ist auch in der Cloud als Docker-Container, AWS- oder Azure-Instanzen und viele andere Cloud-Anbieter verfügbar.

Fordern Sie mit dem unten stehenden Formular eine Testversion an.