2-Lecture : Modern threats to

network security.

Plan

• Why is Network Security Critical today?
• Types of viruses.
• AI powered cyber-attacks.
• Malware
• Social engeneering
• Network and application attacks.
• Defending against network and application attacks
• Digital Infrastructure Threats
• State-sponsored and insider threats
• Advanced –persistant threads (APT s)

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Why is Network Security Critical today?�

• According to Statista, the global cost of cybercrime is projected to rise from $9.22 trillion in 2024 to $13.82 trillion by 2028. 
• This massive increase shows how serious the financial impact of cybercrime has become, exceeding the yearly damage caused by natural disasters and competing with the profits of the illegal drug trade. The escalating threat endangers innovation, business investment and economic stability, stressing the critical need for improved cybersecurity.�

Cost of breaches by industry.

Cost of a breach = the total damage (money, time, reputation, legal impact) a company suffers after a cyberattack or data leak.

Types of Threats Covered:�

• Cyber threats are evolving rapidly, with increasing sophistication.
• Attackers use a mix of technology, social engineering, and sophisticated tools to bypass traditional defenses.
• Malware continues to be prevalent, encompassing various forms such as viruses, ransomware and spyware. These malicious programs can disrupt operations, steal information or damage systems.
• Social engineering exploits human interactions to gain unauthorized access to valuable information and systems. Phishing, one of the most common forms, tricks users into divulging sensitive data.
• Insider threats arise from within an organization and can be accidental or malicious. These threats are particularly insidious as they bypass traditional security measures with legitimate access.
• Advanced persistent threats (APTs) are complex, stealthy and prolonged attacks aimed at specific targets to steal data or disrupt operations, often undetected for long periods.
• Distributed denial of service (DDoS) attacks overload systems with floods of internet traffic. These attacks disrupt services and can serve as a smokescreen for more invasive attacks.
• Ransomware attacks involve encrypting the victim’s data and demanding payment for decryption keys. These attacks can paralyze critical systems and demand significant financial payouts.
• Man-in-the-middle (MitM) attacks intercept communications between two parties to steal or manipulate information.
• Supply chain attacks compromise software or hardware before they reach the consumer, exploiting trusted relationships.

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AI-powered Cyber-Attacks�

• AI-powered cyber-attacks are emerging as a significant challenge in the cybersecurity arena. Cybercriminals are using artificial intelligence to elevate the sophistication and impact of their attacks, making them increasingly elusive and harder to detect. These AI-driven threats can automate vulnerability identification, craft convincing phishing schemes and even adapt in real-time to circumvent security measures.
• The dynamic nature of AI means traditional defenses may no longer be sufficient. This calls for a proactive and innovative approach to cybersecurity. Organizations must prioritize investment in AI-driven security solutions and continuously refine their strategies to stay ahead of these rapidly evolving threats.

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Deepfake Technology�

• Deepfake technology uses artificial intelligence to create realistic fake videos, images or audio that mimic real people, often making it difficult to tell them apart from genuine content. It is quickly becoming a powerful tool for cybercriminals, with almost two-thirds of organizations experiencing a deepfake attack within a 12-year period. 
• Examples of deepfake technology include comedic face swaps on social media, non-consensual pornography, AI-generated fraudulent business communications, manipulated political videos and AI-driven satire or artistic expression.
• �

Malware �

• Malware, or malicious software, has existed since the 1960s and remains a significant threat to cybersecurity worldwide. Today, there are over 1 billion malware programs globally, with approximately 560,000 new threats detected every day.
• Types:
• Viruses: Self-replicating programs that spread to other files or systems.
• Trojans: Malicious software disguised as legitimate software.
• Worms: Malware that spreads autonomously across networks.
• Ransomware: Encrypts files and demands payment to decrypt them.
• Real-World Example: WannaCry ransomware attack.
• Defense Measures:
• Regular patching and updates.
• Antivirus and anti-malware software.
• User training to avoid phishing scams.

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Viruses and Worms

Viruses and worms are some of the oldest types of malware but remain highly effective due to their evolving mechanisms. Viruses attach themselves to clean files and infect other clean files, which can spread uncontrollably, damaging the system’s core functionality and corrupting data. Worms, on the other hand, self-replicate without human intervention and typically exploit vulnerabilities within the system’s network. Recent variations have seen worms that can evade detection by mimicking benign network traffic

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Ransomware (Encrypting viruses)

​Your computer or all data on your network will be locked and a payment will be demanded to unlock it.

​In 2021 the Colonial Pipeline company was attacked. The system stopped working, fuel delivery halted. They paid $4.4 million to retrieve their data.

How can you protect yourself?​✅ Back up important files​✅ Use antivirus programs​✅ Be cautious of fake emails and links

• Cryptojacking
• Cryptojacking is a stealthy threat that remains under the radar but poses significant risks as it hijacks computer resources to mine cryptocurrency. Unlike other forms of malware, cryptojacking focuses on generating revenue without direct theft or data compromise, making it less noticeable but equally damaging in terms of resource utilization.
• Fileless Malware
• Fileless malware leverages scripts or loaded modules into the random access memory (RAM) without writing to the disk, making it difficult for traditional antivirus solutions to detect. This type of attack exploits existing, legitimate programs to execute malicious activities, often bypassing user and endpoint defenses.
• To combat these malware threats, organizations should adopt a layered security approach that includes regular software updates, comprehensive end-user education to guard against phishing, advanced threat detection systems and rigorous access controls. Employing a robust cybersecurity framework and conducting regular audits will help with the early detection and mitigation of these cybersecurity threats.

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Social engineering

• Social engineering remains one of the most insidious types of cyber threats because it exploits human psychology rather than technological vulnerabilities. These attacks trick individuals into breaking normal security procedures, often leading to significant data breaches or financial losses. Here’s how these schemes are evolving in 2026:
• Phishing Variants
• Email phishing: As the most common type of phishing, attackers send mass emails impersonating trusted individuals or organizations to steal credentials, money or sensitive information.
• Spear phishing: Spear phishing targets individuals with highly tailored and convincing messages, often appearing to be from colleagues or trusted sources. For example, attackers might pose as remote tech support agents to address VPN complications, leveraging common workplace issues to manipulate employees during widespread remote work periods.
• Whaling: This is a type of spear phishing that specifically targets high-profile individuals within organizations, such as executives, CEOs and CFOs. 
• Vishing (voice phishing): In vishing scenarios, attackers use phone calls to extract sensitive information under the guise of legitimate requests. A typical scheme involves impersonators claiming to represent a bank, alerting victims about suspicious transactions and coaxing them into verifying personal account details, which can lead to financial theft.
• Smishing (SMS phishing): This technique involves text messages sent under the guise of urgency requiring immediate action such as clicking a link to track an undelivered package. The link, however, redirects the recipient to a malicious site intended to compromise personal data.
• Angler phishing: This is a type of attack that occurs on social media platforms. Attackers create fake accounts that impersonate legitimate brands, customer support teams or well-known individuals. They reach out to users who post complaints or questions, or they respond to public posts with malicious links. The goal is to trick victims into revealing login credentials, personal information or financial details, or to click on a link that installs malware.�

Baiting and Pretexting�

• Baiting: Baiting tactics involve enticing victims with the promise of goods or information. One common method includes distributing USB drives, purportedly containing important work-related data like employee salary lists, which actually contain harmful malware designed to infiltrate corporate networks.
• Pretexting: Attackers often use pretexting to obtain personal information under false pretenses. They might, for instance, pose as surveyors needing confidential data for supposed business or security audits, exploiting the targeted individuals’ trust and cooperative instincts.

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Network and Application Attacks�

• As cyber threats evolve, network and application attacks have become more sophisticated, targeting the very backbone of organizational IT infrastructures. Here’s how these attacks are currently manifesting:
• Man-in-the-Middle (MitM) Attacks
• MitM attacks occur when attackers intercept and alter communications between two parties without their knowledge. These attacks have grown more complex with the increase in encrypted traffic via HTTPS. Attackers often exploit flaws in SSL/TLS protocols or use stolen certificates to decrypt and manipulate communications.
• Injection Attacks
• Injection attacks are prevalent across various platforms, particularly web applications. They occur when an attacker sends untrusted data to an interpreter as part of a command or query. The interpreter then executes unintended commands or accesses data without proper authorization.
• �

Denial-of-Service (DoS) and �Distributed Denial-of-Service (DDoS) Attacks

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• Definition: Attacks designed to overwhelm a system, service, or network by flooding it with traffic, making it unavailable.
• Types:
• DoS: Single-source attack targeting one machine.
• DDoS: Multiple machines or botnets attacking a target.
• Real-World Example: 2016 DDoS attack on Dyn, affecting services like Twitter and Spotify.
• Defense Measures:
• Intrusion detection systems (IDS).
• Load balancers and redundant systems.
• Cloud-based DDoS protection services.

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Defending against network and application attacks requires a multi-faceted approach:�

• For DDoS: Employ comprehensive threat monitoring systems to detect and mitigate attacks before they can cause significant damage. Utilizing rate limiting (which controls the amount and rate of traffic sent or received by a network server), web application firewalls (WAFs) and anti-DDoS hardware and software solutions are critical.
• For MitM: Ensure proper SSL/TLS configurations — cryptographic protocols designed to provide secure communication over a computer network — and keep all certificates up-to-date. Educating users on the security of their internet connections, especially on public networks, is also vital.
• For injection attacks: Implement rigorous input validation, use prepared statements with parameterized queries in databases and regularly review and update codebases to safeguard against vulnerabilities.

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Digital Infrastructure Threats�

• As technology advances, new types of cybersecurity challenges emerge, particularly in the rapidly expanding domains of the Internet of Things (IoT), supply chains and cloud computing. These sectors are increasingly integral to organizational operations and are consequently becoming prime targets for cyberattacks.

Internet of Things Attacks

The Internet of Things encompasses a vast array of devices — from household appliances to industrial equipment — all connected online. These devices often lack robust security features, making them susceptible to attacks. Common vulnerabilities include insecure firmware, weak authentication protocols and unsecured network services. Statista projects IoT devices will nearly double from 19.8 billion in 2025 to more than 40.6 billion by 2045.

For example, IoT devices can be compromised to create botnets that launch massive DDoS attacks. As the IoT continues to grow, securing these devices becomes increasingly critical, necessitating the development of new security frameworks and the adoption of rigorous security practices at the development stage.

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Supply Chain Attacks

Supply chain attacks exploit the interconnected systems of organizations, leveraging trusted relationships to breach multiple entities in a single attack. These attacks are on the rise, with one report noting that one in three organizations experienced increased cyber incidents targeting their supply chains over the past six months.

Cloud Security

As businesses increasingly rely on cloud computing, vulnerabilities in cloud infrastructure have become more apparent. Misconfigurations and inadequate access controls are the most common issues that lead to unauthorized access and data breaches. For instance, improperly configured S3 buckets — a fundamental storage resource in Amazon Web Services (AWS) — have led to significant data losses for even major corporations.

Preventive measures include:

Preventive measures include:�

• IoT security: Regular firmware updates, default credential changes and network segmentation can significantly enhance the security of IoT devices.
• Supply chain security: Continuous vetting, adherence to strict security standards by all parties and integrating security practices into contract agreements are vital.
• Cloud security: Utilization of automated tools to monitor and correct configurations, rigorous access controls and employee training on cloud security best practices are critical for safeguarding cloud environments.

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State-sponsored and Insider Threats�

• As the cyber landscape becomes increasingly politicized and competitive, state-sponsored cyber activities and insider threats have risen sharply, posing sophisticated and stealthy challenges to global security infrastructures.
• Nation-state Cyber Activities
• Nation-state cyber activities often involve operations aimed at espionage, sabotage or influencing global political landscapes. Recent examples include Russian government-sponsored groups targeting critical infrastructure in the United States and Ukraine, primarily through malware and DDoS attacks, to disrupt services and gather intelligence.
• Another example is Chinese cyber units conducting prolonged espionage against technology companies to steal intellectual property and sensitive government data. These operations are characterized by their high level of sophistication, significant state resources and long-term objectives that often align with national military or economic strategies.
• Insider Threats
• Insider threats arise from individuals within an organization who misuse their access to systems and data, either maliciously or through negligence. Strategies to detect and prevent these threats include:
• Behavioral analytics: Implementing user and entity behavior analytics (UEBA) to detect anomalous behavior patterns that may indicate malicious activity or policy violations
• Access controls: Applying the principle of least privilege and regularly reviewing access permissions to ensure that employees only have access to the resources necessary for their job functions
• Regular audits and training: Conducting comprehensive security audits and providing ongoing security awareness training to educate employees about the indicators of insider threats and the importance of following organizational security policies

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Advanced Persistent Threats (APTs)

APTs are complex cyberattacks aimed primarily at stealing information or sabotaging operations, often targeting national governments, infrastructure and large corporations. These threats are executed over extended periods, making them discreet and particularly dangerous due to the strategic planning that underpins them.

Characteristics of APTs

APTs distinguish themselves through their sophistication and persistence, with attackers focusing on achieving their long-term objective by avoiding detection. Here are some defining characteristics of APTs:

• Highly targeted: Attackers spend considerable time and resources to target specific entities or sectors. They tailor their tactics, techniques and procedures (TTPs) based on the vulnerabilities and value of their targets.
• Long-term engagement: Unlike other cyber threats that seek quick hits, APTs involve long durations of engagement with the target’s network, sometimes lasting years to continuously steal data or await the right moment to strike.
• Use of advanced malware: These threats often involve complex malware and spear-phishing attacks to gain initial access and maintain persistence within the target’s infrastructure.
• Evasion techniques: APTs use sophisticated methods to evade detection, including encryption, kill switches and exploiting zero-day vulnerabilities.
• Lateral movement: Once access is gained, APTs move laterally through the network to establish footholds in different parts of the organization’s digital infrastructure.

�

• Specific complex networks are a protection, also known as a firewall.
• TE generally divides the network into two parts: internal and external networks.
• The internal network is the organization’s protected internal network, and the external network is the global internet.

internet.

Clients

Servers

​

TE

Clients

Servers

Open external network

Protected internal network

1. Traffic control and filtering

The main function of a firewall is to manage the flow of data passing through the network. This includes the following:

• Packet filtering: Divides traffic into small units (packets) and examines them based on address, port number, and protocol type. For example:
• Filtering based on TCP (Transmission Control Protocol) or UDP (User Datagram Protocol) protocols.
• Allowing or blocking inbound or outbound traffic.
• Stateful inspection: A firewall monitors not only the current state of traffic but also its previous activity. For example, if an incoming request originated from the internal network, it is allowed; otherwise, it is blocked.
• Application-layer control: Inspects specific applications or services (e.g., email, web browser) and stops those that do not meet security requirements.

2. Ensuring security and protecting the network

Inter-network firewall protects the network from internal and external threats:

• Blocking malicious software: Detecting and blocking threats coming from viruses, trojans, or bots.
• Protection from attacks: Protects the network from various cyber attacks, such as DoS/DDoS (Denial of Service) or malicious traffic attempting to deliberately corrupt incoming data.
• Strengthening the security wall: Implements rules and restrictions so that internal users do not use improper or unsafe resources.

Example: Only connections via HTTPS (encrypted) protocol are allowed to the company's internal network, all other connections are blocked.

3. Separating network boundaries and segmentation

Inter‑network firewall establishes security boundaries between internal, external, and intermediate (DMZ – demilitarized zone) networks.

• Protecting the internal network: Only internal users are allowed access. For example, employees can connect to the servers they work on, but their direct access via the Internet is restricted.
• Protection from external threats: Stops malicious traffic from the Internet before it reaches the internal network.
• Establishing a DMZ zone: Isolates web servers, email servers, or other public services, limiting access to the internal network if they are compromised.

4. Traffic analysis and logging

Network overview:

• Records information about each packet.
• Continuously analyzes traffic flow to detect malicious traffic or attacks.
• Helps administrators monitor any suspicious activity occurring on the network through statistical data.

Example: If an external user attempts to log into the network multiple times with an incorrect password, this event is logged and reported to the administrator.

5. Implementing network rules

The following rules can be implemented using the inter-network firewall:

• Allowing or denying access to specific addresses or protocols.
• Restricting traffic by time of day (e.g., using network resources only during working hours).
• Limiting certain users from accessing specific services (e.g., blocking access to social networks).

Example: Only connections to the company's email server are allowed, while other services (e.g., video streaming) are restricted.

6. Detecting Various Types of Attacks

The inter-network screen works effectively in detecting various attacks and combating them:

• IP spoofing: Blocks attacks carried out by fraudsters using forged IP addresses.
• Port scanning: Detects and stops attempts to discover open ports in the network.
• Zero-day attacks: Provides protection against previously unknown threats using pre-configured settings.

Protected virtual network (Virtual Private Network, VPN)

VPN connects the user's device to the internet through a special encrypted tunnel. This process works in three stages:

1. Encryption:
1. The data transmitted between the user's device and the VPN server is encrypted.
2. This encryption prevents other parties from reading the data.
2. Tunneling:
• The data is routed through the VPN server before being sent to the internet.
• This tunneling process hides the real IP address.
3. Decryption:

The VPN server sends the data to the internet and receives the response data, re‑encrypting it before sending it back to the user's device.

VPN technology is defined by a special set called protocols to ensure secure and efficient data processing. VPN protocols encrypt data, authenticate, and manage processes on the network.

1. PPTP (Point-to-Point Tunnel Protocol)

PPTP is one of the oldest types of VPN protocols, developed by Microsoft in the 1990s.

• Features:
• Very simple and fast.
• Encryption is based on an authentication method.
• Advantages:
• Easy to set up and configure.
• Runs quickly due to low technical requirements.
• Disadvantages:
• Encryption is weak and unprotected against modern attacks.
• Not recommended for active use, as the requirements are low.

2. L2TP/IPSec (Layer 2 Tunnel Protocol)

L2TP tunneling protocol and IPSec (Internet Protocol Security) speed test.

• Features:
• Provides higher security with double encryption.
• Operates over UDP port 1701.
• Advantages:
• Encryption level is considerably stronger compared to PPTP.
• Available on many operating systems.
• Disadvantages:
• Speed is somewhat lower because data is encrypted twice.
• May be blocked by common firewalls.

3. OpenVPN

One of the open-source and most reliable VPN protocols. OpenVPN technology can operate on TCP and UDP ports.

• Features :
• Based on SSL/TLS encryption protocols.
• Has additional modification and configuration options.
• Advantages :
• High level of anonymity.
• Works well against network blocking.
• Easy to get support because it is open-source.
• Disadvantages :
• Installation is somewhat complex.
• Uses more system resources.

4. WireGuard

A modern, high-speed, VPN-providing new protocol.

• Features :
• Very easy and efficient, consisting of 4,000 lines of code.
• Supports modern cryptographic algorithms and identification.
• Advantages :
• Fast operation .
• Easy to configure.
• Fewer errors due to small code size.
• Disadvantages :
• Since it is still new, it is not widely adopted across all systems.
• Some services exist for maintaining privacy.

5. IKEv2/IPSec (Internet Key Exchange 2 version)

IKEv2, together with IPSec, is a fast protocol developed by BlackBerry and Microsoft.

• Features:
• It automatically reconnects (reconnection).
• Works efficiently on mobile networks (4G).
• Advantages:
• High speed.
• Handles network changes (switching from Wi‑Fi to mobile network).
• Disadvantages:
• May not always work on older devices.
• May require additional support.

6. SSTP (Secure Socket Tunneling Protocol)

Developed by Microsoft and a secure protocol on the HTTPS port.

• Features:
• Based on SSL/TLS encryption.
• Difficult to block because it goes through HTTPS.
• Advantages:
• Works well against public firewalls and network throttling.
• Well integrated with Windows systems.
• Disadvantages:
• Designed only for Windows devices.
• Not open source, making independent audits difficult.

7. SoftEther

A university project from Japan, a lightweight VPN technology supporting many protocols.

• Features :
• Supports Open, L2TP/IPSec, SSTP and other protocols.
• High cross‑platform compatibility.
• Advantages :
• Very easy to use.
• Provides extensive support.
• Disadvantages :
• May require more resources.
• Widely popular.

ACTIVE & VULNERABILITY

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Organization's assets

identification can be a long and complex process. This process is one of the most important steps in vulnerability assessment.

IF THE ORGANIZATION DOESN’T KNOW WHAT

TO PROTECT, HOW TO ORGANIZE PROTECTION

IS POSSIBLE???

ASSET

VULNERABILITY

Vulnerability assessment – a systematic and methodological evaluation of the damage that assets may incur from attackers, natural forces, or any other hazards. Vulnerability assessment determines what needs to be protected (identifying assets), how much impact it may have (assessing threats), how weak the current protection is (evaluating vulnerabilities), what damage could result from threats (risk assessment), and what measures are necessary (reducing risk level).

bo‘lgan zararning tizimli va uslubiy bahosi. Zaiflikni baholash nimani himoyalash zarur (aktivlarni identifikatsiyalash), qanchalik taʼsir etishi (tahdidlarni baholash), joriy himoya qanchalik zaif (zaifliklarni baholash), tahdid natijasida qanday zarar yetishi mumkin (riskni baholash) va qanday chora ko‘rish zarur (risk darajasini pasaytirish).

Vulnerability scanner

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Vulnerability scanners are designed to detect vulnerabilities in the organization’s network and alert system administrators about them. Most scanners support a vulnerability database.

• Alert when new elements are added to the network

Detect application breaches;

• identify the scanning process of the external network;

Specifically which

• Ichki tarmoq resurslari tashqi

ports and services for each system

• determine which ports are shown and which ports are being monitored;

confidential

Which applications and servers

determine what they are transmitting;

• Maintain a log of all interactive network sessions;

Operating system type of all active systems

detect in passive mode

• and
• Barcha faol tizimlarning opersion tizimi turini

monitoring

Finding vulnerabilities of all client

kuzatib

• Barcha mijoz

ilovalarining zaifliklarini borish.

Main threat sources

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Penetration Testing

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Penetration testing

Black box.

White box.

Gray box.

In the Black‑box method

the tester has no knowledge about the network infrastructure being tested.

Before conducting real attacks, the tester must determine the type and location of systems and devices.

This allows the organization to simulate real external attacks.

imitatsiyalashga imkon beradi.

The opposite of the Black‑box method

in the White‑box approach

the tester has important information about the network and system being tested, such as network topology, IP addresses, even

users

and the current source code of applications.

Gray box is a method between Black‑box and White‑box, providing the tester with

a limited amount of information.

Unlike vulnerability scanning, penetration testing (also called a pentest) is intended to exploit any weak points in the system.

Penetration testing relies on the tester’s knowledge, skills, and ingenuity rather than on automated tools.

Suqilib kirishga testlashda jarayon avtomatlashgan dasturiy vositalar o‘rniga testlovchi mutaxassisning bilim, ko‘nikma va uddaburonligiga asoslanadi.

Attack objects

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71%

20%

Legal entities

1% 1% _2%

5%

Computers,

servers and network devices

Web resources

Users

Mobile devices

IoT

32%

9%

31%

26%

2%

Individuals

Computers,

servers and network devices

Web resources

Users

Mobile devices

IoT

Attack methods

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2

5

9

2

51

58

6

8

14

14

63

66

0

10

Legal entity

40

50

60

70

Others

Acquisition of personal

Hacking

Web vulnerabilities exploitation

Social engineering

Malicious applications use

20 30

Physical person

Impact Scope of Vulnerabilities

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PORT & PORT NUMBERS

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IP addresses are the primary form of address identification in a TCP/IP network and are used to uniquely identify each network device.

TCP/IP uses numeric values as identifiers for programs and services in this system. They are known as port numbers. Each packet contains the source and destination IP addresses, as well as the source port identifying the originating service on the local system and the destination port identifying the corresponding service on the remote system.

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Port

Port numbers

Because port numbers are 16 bits long, they can have decimal values ranging from 0 to 65,535. TCP/IP categorizes port numbers into three classes:

• Well‑known port numbers (0–1023). Assigned for the most universal applications
• Registered port numbers (1024–49151). Used by other applications that are not as widely employed
• Dynamic and private port numbers (49152–65535). Can be used by any application

Port operation statuses

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Open

the program or service associated with the port is

listening for any instructions. The host system returns a response to the scanner about the service's availability and listening

returns

Closed

no process

is listening. Host

system returns a response that the service is not present and that connection attempts are rejected

Blocked

the host system for this port

means it does not answer any request concerning this port number

Because port numbers are linked to services, if an attacker knows that a specific port is reachable, they can indicate which services are being used. For example, if port 20 is present, the attacker may assume FTP

is being used on the network. Consequently, they can direct their attacks to that service.

Ports scanning

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Penetration testing and vulnerability scanner capabilities

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Thank you for your attention