Security testing for one of the first joint stock commercial banks in Vietnam

Case study VSEC - BLOG

VSEC’s client is one of the first licensed commercial joint stock banks in Vietnam with nearly 300 branches and transaction offices across the country. In order to deliver the finest service possible to their end clients, this company has just begun actively utilizing digital transformation in banking activities. When a breach in information security exposes sensitive company data, the enterprise requires the involvement of a reliable security solution.

Following the data collection procedure, we identified the following distinguishing features of the company:

  • There has never been a thorough evaluation and testing of the information security of the complete IT system.
  • The information security team is currently insufficient to implement a thorough system-wide examination of information security.
  • A lack of an external, objective examination of security measures.

 

VSEC analyzes the situation and then confers with businesses to determine the optimal course of action. Accordingly, VSEC will offer Pentest, an IT security assessment and penetration testing service, to the customer. Server systems, network equipment, internal and external applications, and critical databases are all part of the scope of the project. 

We have uncovered security flaws in our customers’ IT systems with the help of our team of experienced specialists, which has allowed us to paint a more complete picture of our customers’ information safety. Information security risks are reduced, client confidence is maintained, and losses are kept to a minimum while the business benefits from implementation guidance and support.

Providing solutions for customers in the energy sector

Case study VSEC - BLOG

Organizations in the Manufacturing and Energy sectors are always prime targets for hackers. Although VSEC is a member of Vietnam’s leading energy corporation, its customers are no exception this time. The enterprise operates in national key fields, providing, and conducting the business of electric energy services in the Northern provinces.

There is a challenge that the enterprise owning many IT systems at various levels is subject to the regulations on information security of the State management agencies. Therefore, its implementation of information security solutions will have much higher requirements than that of other common enterprises. Like many previous cases seeking the aid of VSEC, this unit also lacks a well-equipped team of specialized personnel in information security to fulfill the requirements of large-scale information security assessment activities. This time, VSEC will have to carefully research and advise on solutions for the enterprise.

Through discussing with the unit and referring to the regulations of the State management agency, VSEC has assessed and tested the information security penetration for the entire IT infrastructure and several critical applications of the unit.

After a period of implementing assessment measures, our experts have detected numerous vulnerabilities in clients’ IT systems, thereby providing a comprehensive overview of the information security for clients. Based on that, they have provided recommendations and supported the client in implementing measures to mitigate information security threats. Moreover, we not only safeguard the client’s reputation but also minimize potential damages to the enterprise.

Security solutions for the pioneering corporation in eco-cities

Case study VSEC - BLOG

The client of VSEC is a major corporation that is the developer of Vietnam’s largest green urban project in the country’s northern region and which also has invested in many different sectors, including but not limited to education, health, clean agriculture, high technology, travel, entertainment, etc.

The cross-industry products are supported by a massive IT infrastructure and a workforce of over 300 personnel.

VSEC faces a difficult problem in maintaining its public business image given that the real estate industry deals with highly personal information about its clients. The company has a large number of servers and workstations, a broad set of operations, a widespread connection system, and frequent upgrades to a huge number of new apps, but no dedicated employees to ensure the security of this infrastructure. 

With nearly 20 years in the industry, we have successfully implemented a wide range of security solutions for clients including:

  • Conduct a comprehensive analysis of the existing IT system and current supported applications.
  • Deploy and monitor all servers and workstations of the enterprise
  • Forewarning and coordinated analysis to forestall data security breaches
  • Launch your account’s management page to take charge of all monitored components.
  • Export periodic reports and overview of information security events

Our experienced team has found security flaws in the client’s IT application system after conducting a Pentest and doing a system analysis. We then provide our clients with guidance and assistance during deployment in an effort to lessen their exposure to information security threats, protect their reputations as well as limit any resulting damage.

Meeting information security needs of Vietnam’s leading energy corporation

Case study VSEC - BLOG

As an energy production enterprise and a member of Vietnam’s leading energy corporation in Vietnam, VSEC operates in national key fields.

Operating in national key fields, owning a level 4 system, and complying with the regulations on information security of the State management agency. Having not yet met the requirements of information security activities as the specialized personnel team in charge of information security is still understaffed

Evaluating and reviewing the entire Information Technology system of the unit. Implementing a monitoring plan for all servers, workstations, and network devices of the unit. Alerting and coordinating to analyze and prevent information security threats.

Detecting vulnerabilities in clients’ information technology systems, thereby providing recommendations and supporting them to reduce information security risks. Monitoring information security 24/7 for clients’ information technology systems, promptly identifying information security problems to take appropriate handling measures. Helping clients meet the requirements and regulations of State agencies on ensuring information security in units operating in national key fields.

Deploying information security monitoring for multinational corporations

Case study VSEC - BLOG

The client is an FDI enterprise, a branch of a global corporation that specializes in the assembling and manufacturing of motorcycles and automobiles. The branch holds a market share in the top motorbike and automobile trading enterprises in the Vietnam market.

Enterprises comply with the general regulations on information security of holding companies. This branch employs external threat monitoring services (data leaks, web phishing, etc.) and monitors the reputation of international suppliers at a high expense. They are building a team in charge of local information security, so they need great support from their partners.

Services for external threat monitoring (data leaks, web phishing, etc.) and reputation monitoring are provided. Coordination and consultation with customers are required to continuously optimize the monitoring process.

VSEC SOC detects and immediately notifies clients of fake website information and the leaked information of customers’ data that is published for sale on the dark web, and dark forum. Provide services with reasonable cost and quality equivalent to international suppliers. Provide services at a reasonable cost and of a similar standard to foreign suppliers. Assist the local team in the process of assuring information security for businesses.

SUPPLY CHAIN ATTACKS – THE DREAD OF BUSINESSES

Cyber world trending VSEC - BLOG

A supply chain attack is a cyber attack that targets an organization through its providers/vendors.

 

Current situation of supply chain attacks

A recent study shows that the supply chain attracts cyberattacks like a magnet. A whopping 97% of companies have been affected by supply chain attacks, with 93% of them admitting that they have been directly attacked due to vulnerabilities within the supply chain. According to an analysis by security provider Sonatype, these software supply chain attacks saw a staggering 650% increase in 2021, with Sonatype recording 12,000 incidents in the same year

“Supply chain attacks are terrifying because they are exceptionally challenging to deal with and because they demonstrate that you are placing your trust in the entire ecosystem,” said Nick Weaver, a security researcher at UC Berkeley’s International Computer Science Institute.

With a well-planned attack, they can disrupt a provider’s consumer network, resulting in hundreds or even thousands of victims. In addition, any firm that develops software or hardware for other organizations might be a potential target for these attackers.

 

Common supply chain attacks

  • SolarWinds SUNBURST backdoor: On December 13, 2020, the SUNBURST backdoor was first revealed. The attack leveraged the widely used SolarWinds Orion IT management and monitoring software to develop a malicious trojan update. Its targets included services running Orion software and the U.S. Department of Commerce. Fortune 500 companies, telecommunications firms, other government agencies, and universities are also likely to be affected. Of particular concern within the SUNBURST backdoor was the targeting of dedicated servers, which are typically less frequently monitored. Preventing attacks like the SUNBURST backdoor requires constant monitoring at all levels of the corporate network.
  • Exploiting vulnerabilities in Log4j: Another way of implementing a supply chain attack is by exploiting vulnerabilities in open source software. Notably, there was an attack where hackers exploited vulnerabilities in Log4j. This attack allows hackers to execute code remotely, including the ability to take full control of the server. Log4j is a zero-day vulnerability that was discovered by hackers before the software provider became aware of it. Since this vulnerability is associated with a part of the open-source library, it could potentially impact any of the 3 billion devices running Java.
  • Attacks on Kaseya VSA Software: The primary goal of a supply chain assault is to exploit the weaknesses of suppliers in order to launch attacks on customers. That’s the method the Revil hacking collective employed when they targeted Kaseya VSA, a customer-facing remote monitoring and management service platform for IT infrastructure. By exploiting a vulnerability in the Kaseya VSA, REvil was able to send ransomware to 1,500 companies that are customers of Kaseya VSA.

 

 

  • Capital One attack and cloud infrastructure security flaws: Not all cyberattacks originate from highly organized groups of hackers; in the case of Capital One (USA), a former Amazon employee used his insider knowledge of Amazon Web Services (AWS) to fraudulently charge $100 million to customer credit cards. The attack demonstrated the risks associated with cloud computing.
  • Vulnerabilities on Personal and Third-Party Devices: In March 2022, American cybersecurity firm Okta disclosed that one of its vendors, Sitel, had been infected by a virus. via an employee using a laptop to perform customer service. Fortunately, the extent of the breach was limited, only two of Okta’s authentication systems were compromised, and no client data or settings were altered. However, through this incident, there is a risk that hackers would target devices belonging to subcontractors or employees who carry their own devices to launch more extensive attacks.

 

How to reduce the risk of cyberattacks on supply chains?

Cyber attacks are a constant threat, and every company and organization in the supply chain needs to be prepared for them. That’s why it’s so important for businesses to strengthen their network security defenses. Listed below is a remedy that institutions can do to shield themselves from and reduce the impact of cyber threats.

Carefully select your suppliers: It is imperative for businesses to verify that their vendors use certified security policies and infrastructure. This should be expressed explicitly in any cooperation agreement between the two parties.

Keep a close eye on software vendors: This is especially important for software with access privileges to company assets.

Restrict access to your data from third parties such as vendors and partners: Having fewer people with access to the data will make it easier to manage and prevent security breaches.

Safeguard the devices used by developers: Set up an endpoint protection platform and endpoint detection and response technologies to see any unusual activity and troubleshoot appropriately if necessary.

Education of staff, vendors, and associates: Organize training seminars to instruct workers on how to properly implement all of the company’s security measures, from password protection to technical assaults. All important matters should not be overlooked.

Always have a backup plan in unexpected cases: While no strategy can guarantee that a crisis won’t occur, you can prepare for it by having an event response plan ready to implement.

To ensure your clients’ faith and patronage of your services, VSEC is present 24/7 to improve the security of the IT infrastructure.

Source: ictvietnam, computerweekly, helpnetsecurity, gep.com

5 subdomain scanners to assist the pentest process

For pentester VSEC - BLOG

In recent years, finding subdomains has become an important part of the pentest process. This mission usually takes time and effort. However, the development of digital technology platforms has provided us with effective tools. This article will outline 5 subdomain scanners to assist in the pentest process.

Outstanding methods for finding subdomains

The finding of subdomains helps in analyzing the domain infrastructure of any company. Let’s find out the most common uses of these tools.

DNS audit

DNS attacks are becoming more and more common, however, most companies are not aware of this threat. Very few companies perform DNS audit regularly although it brings more good things than bad ones. DNS audit can help find DNS vulnerabilities, and update and patch them. In addition, this process can find unused subdomains or potentially vulnerable ones.

 

Domain Intelligence

Red teams often use subdomain discovery took kit in their infosec investigations, which frequently include a number of OSINT techniques. These subdomain enumeration tools detect information exposed to the public such as information about users, apps, or technologies being used in the system.

 

Vulnerability scanning

An extensive list of domain names along with their subdomains can bring a lot of benefits to the process of vulnerability scanning

 

How subdomain scanners work  

Querying search engines

We can use Google to search for subdomains of any domain. Just use the simple command line below:

site:vsec.com.vn -www

This command line will return all the domains indexed by Google.

Most of today’s tools use Google or Bing as built-in modules to assist in searching.

Performing brute force discovery

Some discovery tools use this method for improving search results. While it isn’t the quickest way to find subdomains, it can be one of the most accurate

TLS/SSL information

SSl/TLS certificates are not only useful for encrypting data sent and received between browsers and servers, but it’s also helpful for pentester.

Subject Alternate name (SAN) of SSL/TLS certificate can be used to extract domain and subdomain names

 

Top 5 subdomain scanners (terminal-based)

  1. AMASS

Developed on the Go lang platform, it’s one of the most effective tools in discovering large numbers of subdomain

AMASS uses a variety of subdomain mapping techniques including scraping, recursive brute force, reverse DNS sweeping, and Machine Learning to get the best result. Installing AMASS is quite easy. Installation instructions and manual are available at:  https://github.com/OWASP/Amass

Or can install by using snap (on Kali Linux and other Linux distros), by a command line: snap install amass

After installing, you can use the simple command below to search subdomain: amass enum -d example.com

Result:

User manual: https://github.com/OWASP/Amass/blob/master/doc/user_guide.md

 

  1. SubBrute

This is one of the fastest subdomain discovery tools. One of its coolest features is the ability to conceal the origin of the subdomain scanning itself, by using open resolvers as proxy to DNS rate-limit. 

It can also work as a DNS spider that recursively crawls enumerated DNS records.

SubBrute supports filtering DNS records. For example, if you need to get only TXT records from any given domain name, you can use the –type option:

./subbrute.py -s google.names google.com –type TXT

Another great thing about SubBrute is the fact that it can be integrated into your own python scripts by using the subbrute.run() function. For example:

import subbrute

for d in subbrute.run (“yahoo.com”):

print(d)

For advanced usage, simply run: ./subbrute -h

 

  1. Sublist3r

Sublist3r is another Python-based tool that can be used as a massive subdomain scanner. It’s widely used by bug bounty hunters, as well as blue and red teams across the globe for subdomain data collection.

By querying search engines such as Bing, Yahoo, Google, Baidu, and other 3rd party sources like Netcraft or VirusTotal subdomain database, it can be one of the most effective and fastest tools around when you want to find subdomains.

Sublist3r minimum requirements are Python2 or Python3 versions.

Python 2 recommended version: 2.7.x

Python 3 recommended version: 3.4.x

To get started, you’ll need to clone the Git repo, and then run the installation for some of the dependencies with pip:

pip install -r requirements.txt

That’s it. Now you can perform subdomain scanning tasks:

./sublist3r.py -d securitytrails.com

Expected output:

Github: https://github.com/aboul3la/Sublist3r

 

4. DNSRecon

DNSRecon is one of the most well-known domain reconnaissance scripts. As with almost every other one on this list, it’s written in Python.

It works by checking all NS records for AXFR zone transfers and can be very useful in DNS enumeration for almost any type of record, including MX, SOA, NS, TXT, SPF, and SRV.

It also supports wildcard resolution checking and brute force-based discovery for A and AAAA type-records with wordlists. It can also query Google Dorks to fetch indexed subdomains by GoogleBot.

After downloading the DNSRecon package, you’ll need to install a few required packages with pip:

pip install -r requirements.txt

Then you are ready to test it: :

./dnsrecon.py -d securitytrails.com

Result

Github: https://github.com/darkoperator/dnsrecon

 

5. AltDNS

AltDNS is a subdomain discovery tool based on work with alterations and permutations.

By setting your own wordlist (or using the default wordlist at default altdns/words.tx), as well as using a list of confirmed subdomains, you can run the script to generate both altered or mutated results that may be present in the domain name.

It includes a dataset of 200+ subdomains that can be used to churn out valid subdomains.

After cloning the git project, install requested packages through pip:

pip install -r request.txt

Then you are ready to start using AltDNS:

./altdns.py -i subdomains.txt -o data_output -w words.txt -r -s results_output.txt

Note: subdomains.txt is the actual subdomain list you know already exists, and words.txt is AltDNS’s own wordlist.

You can expect the output to look like this:

MIPS Assembly Language (P2)

Security for Newbie VSEC - BLOG

Gone is the one… the autumn coat is folded

Still hiding a bit of golden sunlight in the flap

My sorrow growing on branches as leaves

Not fall off quickly but wait for another autumn

Hello everyone, it’s me again, an amateur entering the field. Lately, due to being swamped with company projects, I haven’t had the time to explore and write blog anymore ☹. But today, on the occasion of a leisurely day, just like my single status during the winter season – I take some time to continue this ongoing series, hoping you’ll continue reading?).

Arithmetic Computational Instructions.

Addition Instruction.

As far as I know, it includes:

Instruction Example Meaning
add add $1,$2,$3 $1=$2+$3
add immediate addi $1,$2,100 $1=$2+100 It means addition with constant numbers
add unsigned addu $1,$2,$3 $1=$2+$3 Unsigned integer addition,
add immediate unsigned addiu $1,$2,100 $1=$2+100 Unsigned integer addition,

 

Syntax:

For add, addu: <instruction name> <destination register>, <source register 1>, <source register 2>

For addi, addiu: <instruction name> <destination register>, <source register 1>, <constant number>

Specific example:

Compiling the above .c file with the MIPS architecture as follows:

mips-linux-gnu-gcc -O3 -S -mfp32 -march=mips32 Sum.c

Image when compiled to MIPS Assembly.

Why do I declare a signed int, but the assembly output uses addiu? From what I’ve briefly researched online, most compilers tend to use addu and addiu to avoid “overflow” traps. The add and addi instructions seem to be used only when manually coding or in ISAs like x86, ARM…

Subtraction Instruction.

Instruction Example Meaning
subtract sub $1,$2,$3 $1=$2-$3
subtract unsigned subu $1,$2,$3 $1=$2-$3 Unsigned integer subtraction

Syntax:

sub,subu: <instruction name > <destination register> , <register 1>, < register 2>

Specific example: 

Image when compiled to MIPS Assembly.

Multiplication Instruction.

Instruction Example Meaning
Multiply (withoutoverflow) mul $1,$2,$3 $1=$2*$3 Result fits in 32 bits.
Multiply mult $2,$3 $hi,$low=$2*$3 High 32-bit overflow multiplication saved in hi register

– Low 32 bits stored in low register.

Specific example:

Division Instruction

Lệnh Ví dụ Ý nghĩa
Divide div $2,$3 $hi,$low=$2/$3 Kết quả được lưu trong thanh ghi hi

Thươn số được lưu trong thanh ghi low

 

Alright, I’m too lazy to capture images for this part 😄. This is similar to the previous images anyway.

Logic Computational Instructions.

Instruction Example Meaning
and and $1,$2,$3 $1=$2&$3 Bitwise AND
or or $1,$2,$3 $1=$2|$3 Bitwise OR
xor xor $1,$2,$3 $1 = $2 ??$3 Bitwise XOR
nor nor $1,$2,$3 $1 = ~($2 | $3) not of OR Bitwise NOR
and immediate andi $1,$2,100 $1=$2&100 Bitwise AND register, constant number
or immediate or $1,$2,100 $1=$2|100 Bitwise OR register, constant number
xor immediate xori $1, $2,10 $1 = ~$2 &~10 Bitwise XOR register, constant number
shift left logical sll $1,$2,10 $1=$2<<10 Left shift
shift right logical srl $1,$2,10 $1=$2>>10 Right shift

Specific example.

Image when compiled to MIPS Assembly.

Ending Part 2 for the chilly winter here. See you in the next parts ^^.

Vu Van Tien ( aka n0_be3r )

MIPS Assembly Language (P1)

Security for Newbie VSEC - BLOG

First of all, I’d like to warmly welcome all of you who found out about my blog to read what I write here         (＾∀＾●）ﾉｼ. You might wonder why I’m writing about this MIPS assembly language, as it’s not exactly a new topic and I’m writing about it again 🙁. The reason here is that I’m currently interested in researching and exploring the intricacies of IoT devices (especially Wi-Fi routers). So, as you might already know, IoT devices often use the MIPS architecture for their RISC instruction set.

Speaking of instruction sets, there are two types: CISC and RISC.

  • CISC is mainly used in personal computers and servers because its instruction set is extensive and quite complex, leading to resource and power consumption. That’s why IoT devices aren’t so exciting?)
  • In contrast, RISC is less and simpler, consuming fewer resources and less power, making it suitable for IoT devices or mobile devices.

Enough of that babble, let’s dive into today’s main topic.

MIPS assembly language.

After several upgrades, MIPS now has two versions: 32-bit and 64-bit. However, this article and later I will concentrate solely on the 32-bit version because of the simplicity, and I’m also learning about it, so please understand ^^.

MIPS has a total of 32 registers for storing values, numbered from 0 to 31, along with a common convention when used. Among them, register 0 is always hard-assigned with the value 0.

Register Common Name Meaning
$0 $zero The registers always contain the value 0
$1 $at Reserved for assembler
$2 – $3 $v0,$v1 Saves the return values of a function
$4 – $7 $a0-$a3 Saves arguments passed to functions
$8 – $15 $t0 – $t7 Saves temporary variables
$16 – $23 $s0 – $s7 Saves register values
$24 – $25 $t8 – $t9 Similar to registers $8 – $15
$$26 -$27 $k0 – $k1 Reserved for kernel. Not for general use.
$28 $gp Points to the global area (Global Area Pointer)
$29 $sp Stack Pointer
$30 $fp Frame Pointer
$31 $rp Return Address

MIPS Instruction Format:

In some processors, particularly CISC processors, the size of an instruction varies based on the instruction itself and its operands.

However, MIPS, like most RISC processors, employs fixed-length instruction formats. All MIPS instructions are precisely 32 bits long. The fixed-length instructions provide the advantage of simpler instruction fetching, which translates to smaller and cheaper processors. Simpler and smaller leads to faster performance, lower power consumption, and reduced production costs.

Register Instructions:

Register instructions involve two source registers and one destination register.

Register Instruction Format.

Opcode Source 1 Source 2 Destination Shift Amount Function
000000 5 bits 5 bits 5 bits 5 bits 6 bits

 

Explanation:

Opcode (6 bits): This register contains 6 bits set to 0, indicating that this is a register instruction (RI).

Function (6 bits): This register uses 6 bits to differentiate between different instruction types.

Source 1, Source 2 (10 bits): These two registers, each consisting of 10 bits, represent the source registers used for performing computations.

Destination (5 bits): This field stores the computed result.

Shift Amount (5 bits): The number of bits to shift left or right when there’s a bit shift instruction

Example: add $t3, $t4, $t1

Where: $t3 = 11, $t4 = 12, $t1 = 9

000000 01100 01001 01011 00000 10000
RI $t4 $t1 $t3 unused add

 

Jump Instructions

Opcode Target Offset
0001xx 26 bits

 

In the case if the leftmost 6 bits are 00001x, then this is an unconditional jump instruction.

Example:

000010 xxxxxxxxxxxxxxxxxxxxxxxxxx ~ j label

000011 xxxxxxxxxxxxxxxxxxxxxxxxxx ~ jal label

 

Looking at this, you might wonder how, with 26 bits, it’s possible to jump to the 32-bit destination address. The target address expansion to 32 bits occurs dynamically at runtime when the jump instruction is executed. The destination address field converts to a 32-bit address, be occurs at runtime when the jump instruction is executed.

Coprocessor Instructions

If the leftmost 6 bits are 0100xx, the instruction is processed by the coprocessor (an extension for the basic MIPS CPU). The last two bits represent the coprocessor.

Opcode Source 1 Source 2 Destination Shift Amount Function
0100xx 5 bits 5 bits 5 bits 5 bits 6 bits

 

 

Immediate Instructions

If the leftmost 6 bits differ from all above, the instruction is used for the immediate format.

Immediate instructions use one source register, one destination register, and a 16-bit immediate operand.

The immediate operand is limited to 16 bits, allowing unsigned values from 0 to 65535 or signed values from -32768 to 32767 (MIPS processors use two’s complement for signed operands).

Opcode Source Destination Immediate Operand
0100xx 5 bits 5 bits 16 bits

 

For example: addi $t1, $t5, 7

Opcode Source Destination Immediate Operand
001000 sssss ttttt 0000000000000111
addi $t1 $t5 7

 

And that concludes the article. The main purpose of this piece was to provide a brief and general introduction to the MIPS assembly language. In the upcoming articles, I will explai the details of the instructions that I consider crucial within MIPS :D. This will be a long-term series, so if you find it informative, please giving me a like and subscribe ^^.

Reference link:

https://chortle.ccsu.edu/AssemblyTutorial/index.html

https://en.wikipedia.org/wiki/MIPS_architecture

The path from zero to a skilled pentester (part 1)

For pentester VSEC - BLOG

Perhaps this topic is the one that really impresses me. It’s October, the month that I feel warm and ambitious.

This is the sharing of my personal opinion, so if you have different ideas, please feel welcome to email me to discuss

I started as an IT specialist but security is my passion. I used to be a professional programmer and perhaps, my close friends and teachers at Ha Noi University of Science and Technology encouraged me to this field. It’s true that I hadn’t known anything about security before. So in my third year of university, as the requirement of my major, I joined a company for an internship and met my instructor there. This company specialized in information security, but in a short period of three months, I just got some basic stuff about DVWA (Damn Vulnerable Web App) from my instructor to study and attack. By chance, the company Director let me take a field trip for experience. There, I got acquainted with SIEM, to manage events by QRADA, … for a bank. Every day, I came to check the events and emailed my senior to notify me of any abnormalities. It might be a little boring that I decided to resign, frankly speaking, it was the end of my internship and I resigned. Realizing that it was time for further studying and practicing, I decided to pursue Information Security despite not being so sure of what this field was for.

After reading and researching, I found that IT is the broadest field. Information Security is narrower but still quite wide. Information Security is also divided into many areas. When I applied for an internship at the company where I’m working, I was oriented to Pentest (Penetration testing), and deeper into the website Pentest.

 

First, we need to understand what pentest is. Pentest stands for Penetration Testing, which means “An authorized simulated attack performed on a computer system to evaluate its security”. More simply, pen-testers can be considered as the hackers in black, wearing masks to attack the system. Such an explanation makes it easier to imagine. As far as my knowledge, pentest can be divided into 3 following areas:

  • Evaluation of network infrastructure: network structure, policies (firewall), logging, VPN, Router, Switch,…
  • Evaluation of servers system: Configuration, services update, patches, account and password policies, logging policies, authorization review, reserved capacity, load balancing, distributed database.
  • Evaluation of website apps: evaluation of vulnerabilities such as buffer overflow, SQL injection attack, and XSS,… evaluation of the checking of web source codes in order to identify problems on authentication, authorization, data verification, session management, and encryption. In my opinion, we should call this “apps evaluation” because, besides web apps, there are other ones such as mobile,… 

 

There are 2 concepts that many people may still be confused about vulnerability and threat.

  • Vulnerability: weak points in the system that can be exploited and manipulated to cause damage to the system
  • Threat: behaviors that are potentially harmful to the system,

So, What are the types of pentest?

  • Black box pentest: This is a kind of evaluation from the outside to the inside. Pentesters have no information about the target system other than what has been publicized. This is the most common type of attack.
  • Gray box pentest: Pentesters will be provided some or limited information about the target system
  • White box pentest: Evaluation from inside to the outside, Pentesters will be provided all system and network information such as: network infrastructure, source code, IP address details, OS, and policies,…

 

Next, I will discuss the procedure of an attack which can be summarized in three stages:

Prepare for attack:

  • Reconnaissance/Footprinting
  • Scanning

Conduct the attack

  • Gaining access
  • Maintaining access

Clearing tracks

In details:

Reconnaissance/Footprinting
  • Actions of the attacker to gather information about the system: users, customers, business activities, organizational information…
  • Can be repeated periodically until there is an easier chance to attack
  • Active reconnaissance: Interact with the target
  • Passive reconnaissance: not interact with the target: Social Engineering
  • Search engine: Google, Shodan, Censys
  • Information from social networks: Facebook, Twitter, Linkedin
  • Email reconnaissance: whois/smartphones, Email Extractor
  • Internet connection reconnaissance: traceroute
  • DNS information: dnsenum / nslookup, dnswatch.info
  • File robots.txt: This is the file for… Google
  • What web
  • DNS-enum
  • The harvester: gathering emails, names, subdomains, Ips, and ULRs
  • Email extractor

 

Scanning
  • Scanning to identify information of the system based on information gathered from the reconnaissance stage
  • The attacker will get an in-depth and more detailed view of the system: services provided, open service ports, IPs, OS, and software.
  • Extraction information from this stage allows the attackers to plan details for the attack.

 

Gaining Access
  • The attackers with information gathered from the previous stage will conduct the attack on the system to gain access using web security gaps such as SQLi, RCE,…

 

Maintaining Access
  • Once access has been gained, the attacker will use some techniques to maintain access without relaunching the attack such as creating a back door, opening a network connection,…

 

Clearing Tracks 
  • This is an important stage to clear tracks of your penetration into the system so that no one can detect it. It will be very difficult for the investigator to identify who you are or what you have done as you have deleted the system logs,…

 

Seem like a lot of theories, but it’s the door to Pentester

For myself, first, I did a thorough research about the above contents. Next is to choose the way and I have chosen the mobile and website application Pentest.

In this section, my presentation about the path focuses on the evaluation of website applications.

During the internship at the company, I first learned about the network starting with OSI and TCP/IP reference model, the TCP three-way handshake process, using Wireshark, nmap, hping.

This is the introduction step about the network. Going deeper into the website, you need to understand website technology, Client, Server, HTTP protocol, URL, URI, and what headers in HTTP protocol are used for.

The first book I came across was:

“The Web Application Hacker’s Handbook”.

Theory should be combined with practice to study and install environments such as DVWA, BWAPP (I found it far more interesting and difficult than DVWA),… Finishing BWAPP, you will have the background knowledge because BWAPP follows the OWASP assessment standard, the famous name is OWASP Top Ten. By trying to study these labs and always asking “Why”, you will get a better understanding.

If you don’t want to build a lab, you can learn here, There’s a lab and tutorial, and I think they are quite good:  

https://portswigger.net/web-security

After gaining enough background knowledge, you can take CTF tests to improve your skills.

I personally go straight forward to bug bounty programs instead of taking CTF. These programs offer rewards when you find bugs and report to them. The most important thing here is “money”- which motivated me to fight. Right, when you have high motivation, you will try and fight with all your best. When first joining such programs,  you should choose easy targets for gradual learning. In my case, the company had this kind of program in private form for people to participate. In addition, there are public programs in Vietnam that you can find out for yourself, In the world, some famous programs are:

https://hackerone.com/

https://www.bugcrowd.com/

One more thing, You guys who have been reading my blog can see that I always talk about CVE, right? CVE seemed too luxurious for me before, but I have overcome myself and improved my knowledge to look for it and find open sources to install and run it. The most important thing is to choose my favorite language. I personally prefer PHP,… with CMS like WorldPress, Joomla!, Drupal,…

In addition to CVE, you can pursue more advanced education for such certificates as OSCP, OSCE, AWAE,… or learn about other certificates like GPEN,…

There is a very valuable information source on GitHub:

https://github.com/swisskyrepo/PayloadsAllTheThings

Maybe, it is mind

https://github.com/HoangKien1020/pentest

TOP 4 RANSOMWARE VULNERABILITIES EXPOSING YOUR COMPANY AT RISK

Cyber world trending VSEC - BLOG

In 2023, there are two organization groups: those having been attacked by ransomware and those that will shortly be targeted. The current state of cybersecurity resembles an ongoing cyber arms race between ransomware groups and cybersecurity professionals. Experts in cybersecurity have developed the necessary tools and strategies to combat ransomware groups. This cat-and-mouse game is an endless war of attrition with no distinct victor. While in some aspects the situations are probably out of the IT team’s control, there are a number of measures that can be taken to reduce the risks of successful ransomware attacks.

According to research from Securin, hundreds of organizations’ security vulnerabilities are asserted to be exposed. A brief overview of the four most prevalent categories that should be well aware of is listed as follows.

 

1- Vulnerability allowing intruders to enter the network

According to the research conducted by Securin, external tele services, VPNs, and public apps contain 133 ransomware-related vulnerabilities that can be exploited for initial access.

External tele services including Windows Server Message Block (SMB) and Microsoft Remote Desktop Protocol, since the pandemic’s outbreak and the evolution of work-from-home (WFH), have become more common. Some of them with misconfigurations or popular exploited technology, are easily attacked. For instance, one of the largest ransomware attacks in history, WannaCry in 2017, exploited the SMB vulnerability. In addition to the Log4Shell vulnerability affecting 176 products from 21 vendors and having been exploited by six ransomware groups, including Conti and AvosLocker, there are many other unpatched ones.

 

2- Vulnerability requiring user’s action

It is noted that “vulnerability” not only relates to software or hardware problems but also to user mistakes. In fact, a significant proportion of ransomware attacks result from this factor. By acting as a friend, colleague, or supervisor of the victim for example, ransomware groups are able to achieve their objectives. Users may inadvertently enter malicious code when accessing email attachments, links, or files. Unfortunately, users become more observant. Now it is the turn of the thief to modify their tools.

The human problem requires human solution response: intensive face-to-face proper training in which IT team members instruct employees from other departments on how to identify potential threats (and what to do if they accidentally allow someone into the system). It is imperative that IT departments stay social-technology-trend-updated and routinely inform the company of what to be cautious.

 

3- Vulnerability allowing advanced access

The vulnerabilities that have been discussed thus far mention methods hackers attempt to breach into your network. Sadly, it is usually the first step only. Once hackers have exploited vulnerabilities to gain access to your system, they can exploit additional vulnerabilities— those permit privilege escalations—to execute malicious software and take deeper control of the network. In other words, if the hackers have enough understanding of active vulnerabilities in your system, they can approach a restricted account and become an admin whose access to more sensitive data.

According to Securin’s research mentioned above, there are 75 ransomware-related vulnerabilities that could allow ransomware groups to escalate privileges and facilitate movement across organizational domains, including the Privilege Escalation attack of Windows CLFS and Microsoft Exchange Server.

 

4- Vulnerability allowing stealthy access

Hackers have been employing techniques such as disabling security software or preventing script execution from breaking into vulnerable networks without being detected. Mark-of-the-web bypass (T1553.005), is a typical example that ransomware groups apply to exploit certain file formats and override controls.

Or, BlackByte, a new ransomware group about which the FBI issued a warning last year, according to ZDNet, is famous for a technique “allowing attacks to bypass security products’ detection by exploiting vulnerabilities in more than 1,000 drivers of anti-virus software.” This issue, considered as “Bring your own drivers”, shows a significant and alarming aspect during the war against ransomware attacks.

Ransomware considerably increases and every organization, regardless of field or size, may face such attacks as no system could guarantee to be completely protected. What organizations can do is avoid simple errors through appropriate employee training, a deeper understanding of their systems’ vulnerabilities, and appropriate solutions. The war against ransomware may not end soon, but we can take measures to limit the losses.

According to Cyber Security