• Home
  • Cyber Crime
  • Cyber warfare
  • APT
  • Data Breach
  • Deep Web
  • Digital ID
  • Hacking
  • Hacktivism
  • Intelligence
  • Internet of Things
  • Laws and regulations
  • Malware
  • Mobile
  • Reports
  • Security
  • Social Networks
  • Terrorism
  • ICS-SCADA
  • POLICIES
  • Contact me
MUST READ

Operation CargoTalon targets Russia’s aerospace with EAGLET malware,

 | 

Unpatched flaw in EoL LG LNV5110R cameras lets hackers gain Admin access

 | 

Koske, a new AI-Generated Linux malware appears in the threat landscape

 | 

Mitel patches critical MiVoice MX-ONE Auth bypass flaw

 | 

Coyote malware is first-ever malware abusing Windows UI Automation

 | 

SonicWall fixed critical flaw in SMA 100 devices exploited in Overstep malware attacks

 | 

DSPM & AI Are Booming: $17.87B and $4.8T Markets by 2033

 | 

Stealth backdoor found in WordPress mu-Plugins folder

 | 

U.S. CISA adds CrushFTP, Google Chromium, and SysAid flaws to its Known Exploited Vulnerabilities catalog

 | 

U.S. CISA urges FCEB agencies to fix two Microsoft SharePoint flaws immediately and added them to its Known Exploited Vulnerabilities catalog

 | 

Sophos fixed two critical Sophos Firewall vulnerabilities

 | 

French Authorities confirm XSS.is admin arrested in Ukraine

 | 

Microsoft linked attacks on SharePoint flaws to China-nexus actors

 | 

Cisco confirms active exploitation of ISE and ISE-PIC flaws

 | 

SharePoint under fire: new ToolShell attacks target enterprises

 | 

CrushFTP zero-day actively exploited at least since July 18

 | 

Hardcoded credentials found in HPE Aruba Instant On Wi-Fi devices

 | 

MuddyWater deploys new DCHSpy variants amid Iran-Israel conflict

 | 

U.S. CISA urges to immediately patch Microsoft SharePoint flaw adding it to its Known Exploited Vulnerabilities catalog

 | 

Microsoft issues emergency patches for SharePoint zero-days exploited in "ToolShell" attacks

 | 
  • Home
  • Cyber Crime
  • Cyber warfare
  • APT
  • Data Breach
  • Deep Web
  • Digital ID
  • Hacking
  • Hacktivism
  • Intelligence
  • Internet of Things
  • Laws and regulations
  • Malware
  • Mobile
  • Reports
  • Security
  • Social Networks
  • Terrorism
  • ICS-SCADA
  • POLICIES
  • Contact me
  • Home
  • Breaking News
  • Security
  • Possible attacks on the TCP/IP protocol stack and countermeasures

Possible attacks on the TCP/IP protocol stack and countermeasures

Pierluigi Paganini May 07, 2021

Let’s look at what types of threats each layer of the TCP/IP protocol stack may be susceptible to.

The task of a computer security system is to safeguard the information transmitted over the network and to adequately preserve the data stored in it. 

Excluding in this discussion threats due to natural disasters, we can classify the man-made risk, to which an information system is subject, into intentional threats or unintentional threats due to negligence or inexperience.

Businesses need to protect themselves from these threats, which can put both applications and assets at serious risk.

Intentional human threats can come from individuals with an interest in acquiring information or limiting the operation of business processes, driven by the pursuit of financial or political gain, or simply for fun.

An intentional attack can come from individuals outside the organisation or from internal staff such as ex-employees, disgruntled employees or malicious actors. In fact, personnel who are familiar with the security systems and the structure of the information system and who have the authorisation to access the system itself, can get hold of information or insert malicious code more easily.

The development of the Internet and the distributed processing of information over shared lines has certainly made security a necessary duty. Therefore, the corporate network, if not adequately protected, could be subject to unauthorised access with possible network compromise and information theft.

Network communication vulnerabilities

Network communication on the Internet follows a layered approach, where each layer adds to the activity of the previous layer according to the TCP/IP implementation paradigm. The TCP/IP protocol stack has only 4 layers compared to the standard ISO/OSI protocol (Application, Presentation, Session, Transport, Network, Data link, Physical), namely the Application, TCP, IP and Network Access layers.

According to this model, any data, divided by the host into packets on the 4 layers, is sent to the remote recipient host along a network path that includes many intermediate nodes. Each of these layers can be susceptible to certain types of attacks that exploit system, controls, and security policies vulnerabilities. 

Let’s look at what types of threats each layer may be susceptible to.

The Application Layer which is the highest layer of the stack and closest to the users and its function is to interface and provide services for application processes. It also contains standard and native applications such as Telnet, SMTP, FTP. For these reasons, this layer can be vulnerable to phishing (scammers can pass themselves off as a legitimate contact trying to steal information) and hijacking (a valid user session is exploited to gain unauthorized access to the system).

The TCP layer (Transport layer) is responsible for transporting data, dividing it into packets and handling transmission errors. A classic attack to which this layer can be subject is the Denial of Service that is implemented to disable, interrupt or damage a website, a service or the communication of an entire network by saturating the transmission bandwidth. On the other hand, a typical attack scenario to which the IP layer can be subject, which is in charge of managing data addressing through their transmission on the network, is the so called Man in the Middle attack.

Finally, the network access layer incorporates two ISO/OSI layers, the data link and the physical channel, respectively. The data link, which is the interface between the network card and the transmission medium, is responsible for specifying how data should be sent regardless of the network type. Spoofing that masks an unknown source as legitimate and trusted in a network communication could pose a real threat to this layer: ARP spoofing, for example, allows manipulation at the data link layer to fool higher layer protocols. For the physical channel that is responsible for converting digital data over the transmission medium (e.g., copper cable/electrical pulses or fiber optics/light modulation), packet sniffing techniques, by allowing the capture of data circulating over the network, can pose a real threat to the confidentiality of communications.

How mitigate the damage (countermeasures)

Defence tools cannot provide total and impenetrable protection, but they can certainly make it more difficult and costly to carry out an attack, detect its execution and mitigate the damage.

Here are some:

  • Firewall. The Firewall is a hardware/software tool whose purpose is to protect a host or a network segment from potentially harmful traffic coming from the external network (e.g. Internet). This tool can operate at different levels of the ISO/OSI protocol stack: Application (Application Layer Firewall), TCP (Stateful Firewall), IP (Network Layer Firewall) and Data Link layers (Bridge Firewall).
  • Intrusion Detection System (IDS). An IDS is a tool to detect possible unwanted manipulation of a particular system or network. It can be implemented at different levels of the ISO/OSI protocol stack to detect, for instance, sniffing attempts (Network access Layer) or DoS attacks (TCP Layer).
  • Protocol security. In general, it’s very difficult to ensure that traffic on a network is not intercepted. Therefore, one solution might be to encrypt the transmitted data so that it’s not intelligible in case of sniffing. In this case, a VPN (Virtual Private Network) can be used to create a secure communication network through the Internet, which is by definition not secure. Basically, after an authentication phase, the encapsulated network packets, which travel along a virtual tunnel, are encrypted and decrypted at both ends of the VPN network. Encapsulation and tunneling can be implemented on different layers of the ISO/OSI stack, and each protocol with its own specifics can help protect transmitted data. Among the most common protocols are PPTP and L2PT (Data link layer), IPSEC (Network layer), SSL/TLS (Transport layer) and HTTPS (Application layer).
  • Security analysis. It’s possible to monitor and evaluate the policies adopted by a company through a security audit.  To carry out this operation, which can only be performed from within the company network, it’s necessary to have a complete knowledge of all the network resources to be examined. Without having to know the characteristics of the infrastructure in advance, as an alternative or in conjunction with the security audit, a penetration test can be implemented to simulate an attack from outside the network.
  • Security awareness. Raising awareness of the various aspects of IT security, to increase the level of user awareness, is more essential than ever to improve the organisation’s level of protection. The purpose of an adequate security awareness programme is to provide users (employees and managers) with basic skills, establishing appropriate prevention guidelines and rules of conduct, also with internal/external training, newsletters and company intranets.

About the author: Salvatore Lombardo

IT officer, ICT expert, Clusit member

If you want to receive the weekly Security Affairs Newsletter for free subscribe here.

Follow me on Twitter: @securityaffairs and Facebook

[adrotate banner=”9″][adrotate banner=”12″]

Pierluigi Paganini

(SecurityAffairs – hacking, TCP/IP)

[adrotate banner=”5″]

[adrotate banner=”13″]


facebook linkedin twitter

Hacking networking TCP/IP

you might also like

Pierluigi Paganini July 25, 2025
Operation CargoTalon targets Russia’s aerospace with EAGLET malware,
Read more
Pierluigi Paganini July 25, 2025
Unpatched flaw in EoL LG LNV5110R cameras lets hackers gain Admin access
Read more

leave a comment

newsletter

Subscribe to my email list and stay
up-to-date!

    recent articles

    Operation CargoTalon targets Russia’s aerospace with EAGLET malware,

    Intelligence / July 25, 2025

    Unpatched flaw in EoL LG LNV5110R cameras lets hackers gain Admin access

    Security / July 25, 2025

    Koske, a new AI-Generated Linux malware appears in the threat landscape

    Malware / July 25, 2025

    Mitel patches critical MiVoice MX-ONE Auth bypass flaw

    Security / July 25, 2025

    Coyote malware is first-ever malware abusing Windows UI Automation

    Malware / July 24, 2025

    To contact me write an email to:

    Pierluigi Paganini :
    pierluigi.paganini@securityaffairs.co

    LEARN MORE

    QUICK LINKS

    • Home
    • Cyber Crime
    • Cyber warfare
    • APT
    • Data Breach
    • Deep Web
    • Digital ID
    • Hacking
    • Hacktivism
    • Intelligence
    • Internet of Things
    • Laws and regulations
    • Malware
    • Mobile
    • Reports
    • Security
    • Social Networks
    • Terrorism
    • ICS-SCADA
    • POLICIES
    • Contact me

    Copyright@securityaffairs 2024

    We use cookies on our website to give you the most relevant experience by remembering your preferences and repeat visits. By clicking “Accept All”, you consent to the use of ALL the cookies. However, you may visit "Cookie Settings" to provide a controlled consent.
    Cookie SettingsAccept All
    Manage consent

    Privacy Overview

    This website uses cookies to improve your experience while you navigate through the website. Out of these cookies, the cookies that are categorized as necessary are stored on your browser as they are essential for the working of basic functionalities...
    Necessary
    Always Enabled
    Necessary cookies are absolutely essential for the website to function properly. This category only includes cookies that ensures basic functionalities and security features of the website. These cookies do not store any personal information.
    Non-necessary
    Any cookies that may not be particularly necessary for the website to function and is used specifically to collect user personal data via analytics, ads, other embedded contents are termed as non-necessary cookies. It is mandatory to procure user consent prior to running these cookies on your website.
    SAVE & ACCEPT