3. Samba
• Free software re-implementation of the SMB networking protocol
• File and print services for various Microsoft Windows clients
• Integration with a Microsoft Windows Server domain, either as a Domain
Controller (DC) or as a domain member
• Version 4 Active Directory and Microsoft Windows NT domains
• Runs on most Unix-like systems, such as Linux, Solaris, AIX and the BSD variants,
including Apple's macOS Server, and macOS client (Mac OS X 10.2 and greater).
• Runs on a number of other operating systems such as OpenVMS and IBM i.
• Samba is standard on nearly all distributions of Linux and is commonly included as
a basic system service on other Unix-based operating systems as well.
• Samba is released under the terms of the GNU General Public License.
• The name Samba comes from SMB (Server Message Block), the name of the
proprietary protocol used by the Microsoft Windows network file system.
4. Security of Samba
• Some versions of Samba 3.6.3 and lower suffer serious security issues which can
allow anonymous users to gain root access to a system from an anonymous
connection, through the exploitation of an error in Samba's remote procedure
call.
• On 12 April 2016, Badlock, a crucial security bug in Windows and Samba, was
disclosed.
• On 24 May 2017, it was announced that a remote code execution vulnerability
had been found in Samba named EternalRed or SambaCry, affecting all versions
since 3.5.0.
• On 14 September 2020, a proof-of-concept exploit for the netlogon vulnerability
called Zerologon (CVE-2020-1472) for which a patch exists since August was
published.[27] Some federal agencies using the software have been ordered to
install the patch.
5. File Transfer Protocol (FTP)
• Standard communication protocol used for the transfer of computer files from a
server to a client on a computer network.
• Built on a client–server model architecture using separate control and data
connections between the client and the server
• FTP users may authenticate themselves with a clear-text sign-in protocol,
normally in the form of a username and password, but can connect
anonymously if the server is configured to allow it.
• For secure transmission that protects the username and password, and encrypts
the content, FTP is often secured with SSL/TLS (FTPS) or replaced with SSH File
Transfer Protocol (SFTP)
6. File Transfer Protocol (FTP)
• The first FTP client applications were command-line programs and are still
shipped with most Windows, Unix, and Linux operating systems.
• Many dedicated FTP clients and automation utilities have since been developed
for desktops, servers, mobile devices, and hardware.
• FTP has been incorporated into productivity applications such as HTML editors
and file managers.
• An FTP client used to be commonly integrated in web browsers, where file
servers are browsed with the URI prefix "ftp://".
• Throughout 2021, the two major web browser vendors removed this ability
7. Data transfer modes in FTP
• Stream mode (MODE S):
• Data is sent as a continuous stream, relieving FTP from doing any processing.
• Rather, all processing is left up to TCP.
• No End-of-file indicator is needed, unless the data is divided into records.
• Block mode (MODE B):
• Designed primarily for transferring record-oriented files (STRU R), although can also
be used to transfer stream-oriented (STRU F) text files.
• FTP puts each record (or line) of data into several blocks (block header, byte count,
and data field) and then passes it on to TCP.
• Compressed mode (MODE C):
• Extends MODE B with data compression using run-length encoding.
8. Security in FTP
• FTP was not designed to be a secure protocol, and has many security weaknesses.
• In May 1999, the authors of RFC 2577 listed a vulnerability to the following problems:
• Brute-force attack
• FTP bounce attack
• Packet capture
• Port stealing (guessing the next open port and usurping a legitimate connection)
• Spoofing attack
• Username enumeration
• DoS or DDoS
9. Network File System (NFS)
• A distributed file system protocol originally developed by Sun Microsystems
(Sun) in 1984, allowing a user on a client computer to access files over a
computer network much like local storage is accessed.
• NFS, like many other protocols, builds on the Open Network Computing Remote
Procedure Call (ONC RPC) system.
• NFS is an open IETF standard defined in a Request for Comments (RFC),
allowing anyone to implement the protocol.
10. Version of NFS
• NFSv1
• for in-house experimental purposes
• NFSv2
• operated only over User Datagram Protocol (UDP)
• NFSv3
• Support 64 bits file sizes
• WebNFS
• Allowing it to function behind restrictive firewalls without the complexity of Portmap and MOUNT
protocols.
• WebNFS had a fixed TCP/UDP port number (2049)
• NFSv4
11. Apache HTTP Server
• Free and open-source cross-platform web server software
• Developed and maintained by an open community of developers under the
auspices of the Apache Software Foundation.
• The vast majority of Apache HTTP Server instances run on a Linux distribution
but current versions also run on Microsoft Windows, OpenVMS and a wide
variety of Unix-like systems
• As of March 2022, Netcraft estimated that Apache served 23.04% of the million
busiest websites
12. Security of Apache HTTP Server
• Can be hacked and exploited.
• The main Apache attack tool is Slowloris, which exploits a bug in Apache
software.
• It creates many sockets and keeps each of them alive and busy by sending
several bytes (known as "keep-alive headers") to let the server know that the
computer is still connected and not experiencing network problems.
• The Apache developers have addressed Slowloris with several modules to limit
the damage caused
13. Docker
• Set of platform as a service (PaaS) products that use OS-level virtualization to
deliver software in packages called containers.
• The service has both free and premium tiers.
• The software that hosts the containers is called Docker Engine.
• It was first started in 2013 and is developed by Docker, Inc.
