Really? Haha, No…


Over the weekend, I participated in GoogleCTF2017, my first Capture The Flag (CTF) event. It was both humbling and exciting.  

If you asked me three days ago what was the absolute worst thing someone could say to me, I would have given a completely different answer than today, but today, my answer is ‘Really? Haha, no…’ a phrase I heard way too many times as I worked through the challenges trying to find flags.

In a CTF, each team has a set of challenges that needs to be solved in order to find the flag and grab the points. The flag is usually a piece of code =>CTF{this-is-a-flag}<=.  

CTF competitions touch on many aspects of information security including cryptography, steganography, reverse engineering, forensics, and other topics.

There are three common types of CTFs 

  • Attack and Defend
    • Red Teams (Offense) vs. Blue teams (Defence) actively attacking and defending network infrastructures.
  • Jeopardy.
    • Challenges are broken up into multiple topics ranging from easy to difficult, to insane. 
  • Mixed.
    • Varied formats. Depends upon the host of the event.

GoogleCTF2017 was set up as a Jeopardy-style event, and it turns out that I knew more than I thought; Moreover, it was a wonderful experience competing against peers and picking up mad new skills while expanding upon my security knowledge.

In order to increase my skills in preparation for this CTF (and many others to follow), I used the websites below to practice and train.

As a Front-end developer, knowing how to exploit your own web applications before a cyber criminal can is critical and Google Gruyere is an invaluable resource. You ‘learn by doing’ and in that process, you come to understand how applications can be attacked using cross-site scripting vulnerabilities (XSS) and cross-site request forgeries (XSRF). Additionally, it allows the user(s) to find, fix, and avoid vulnerabilities and other bugs that have an impact on security including

  • Denial-of-service (DoS)
  • Information disclosure.
  • Remote code execution.

However, the greatest part of the weekend I have neglected to mention so far was the elation you feel when you use tactics and exploits to find a flag, and it works, i.e., ‘you have successfully hacked something, and you captured a flag.’ Today, I realized, I belong in this field.


995 points, six challenges, ten hours, two days.

  • 1 Miscellaneous
    • Start Here (FAQ)
  • 3  Crypto Challenges
    • Crypto Backdoor
    • Introspective CRC
    • Shake it
  • 1 Pwn
    • Inst Prof
  • 1 Web
    • Joe

You don’t have to be an expert in order to compete in a CTF. You just need an unrelenting curiosity and passion to never quit!  The purpose of the competition, besides capturing the flag,  is to recognize your strengths and more importantly your weaknesses. CTFs require a great deal of work and dedication but are highly rewarding. Strive for excellence.


‘Know Thy Enemy,’ Distributed Denial of Service or DDoS.


We all know the axiom ‘know thy enemy’ – and this is above all germane to DDoS attacks.

Cybercriminals and their tactics are always evolving, becoming more dangerous and harder to detect by the day.

Unlike a Denial of Service (DoS) attack, in which a single Internet-connected device causes disruption and destruction. DDoS attacks are launched from numerous compromised devices, often dispersed globally in what is referred to as a botnet and controlled remotely by the botnet herder using a covert channel, such as Internet Relay Chat (IRC).

Some of the larger botnets whose name comes from the malware used to infect them are estimated to be in the millions of bots including  Zeus or ZbotConficker, and BredoLab or Oficla to name a few.

It is estimated that upwards of 3000+ websites fall victim to DDoS attacks daily. Regardless if the websites are back up and running the same day, damages to both revenue and customer and/or client trust can follow organizations for years.

The primary purpose of the DDoS is to overload network layers with a substantial amount of outwardly legitimate traffic.  Ultimately the traffic consumes a disproportionate amount of bandwidth within and/or outside of the network and pushes network operations to become excruciatingly sluggish or basically nonfunctional.

Adding to the confusion, botnet servers can be controlled either by a single botnet herder or by multiple herders. Ultimately, at any given DDoS attack there can be multiple origins and multiple controllers making it much more complicated to mitigate than attacks originating from a single source.

The aggressiveness of DDoS attacks was illustrated last year by the Mirai Botnet in which the attacks besieged several systems using corrupted Internet of Things (IoT) devices. iot

The expectation of IoT is upwards of 25 Billion televisions, refrigerators, watches, thermostats, and other connected devices by 2020; most with minimum to zero security in order to prevent malware infections. Resulting in an unknown amount of IoT devices ending up as mindless bots caught up in a criminal botnet.

To make matters worse, roughly 40 percent of malicious bots are able to emulate human behavior. Not only do the malicious bots deceptively present themselves to websites as legitimate bots, but they can also persistently change identities.

The infrastructure which enables these attacks is also increasing rent_a_botnet_ddos_for_hire_botnet_service_02dramatically. Anyone with mal intentions can easily purchase on-demand botnet services for DDoS attacks.

They are readily available from multitudes of online sources; for as little as $5 an hour to $40 per day; Cloaked behind the definition of  Booters or stressers services.

They are also referred to as ddoser, ip stresser, ddos tools and ddos programs. No matter the name, they all provide the same service- providing paying customers with on-demand DDoS attack capabilities, at will.

Below find some of the more well-known Booters and Stressers which are easily accessed on the Internet.

120GB/s of combined power. Takes down everything. Working Skype resolver. Active support. Multiple payment options.

100GB/seconds. Easy to use. API. Insane Power. Accepts Paypal.

Good Power. Easy to use source. PayPal/Credit cards and 15% off Bitcoin. Build Your Plan.

There are three standard types of DDoS attacks including Volumetric, Application, and Protocol attacks.

Volumetric Attacks utilize massive amounts of traffic inundating the bandwidth of the host.

Volumetric attacks are generated by employing amplification techniques which primarily elicit server responses that are disproportionate to the original packet request sent; ultimately completely blocking access to a website or service. The extent of the attack is measured in either bits or packets per second. Domain Name System Servers (DNS) Amplification being a well known volumetric attack.

DNS amplification is an asymmetrical attack in which the dns amplificationcriminal exploits vulnerabilities in DNS servers, i.e., ‘The Internet’s Backbone’ by manipulating publically-accessible domain name system servers by querying the DNS with spoofed or ‘faked’ target IP’s and making them flood a server with large quantities of User Datagram Protocol (UDP) packets.

This results in small queries being turned into massive payloads that can ultimately be used to bring down even the most robust server(s).

Moreover, DNS amplification attacks often relay the exploited DNS requests through one or more botnets, radically increasing the volume of traffic and making it that harder to track the attacker(s) identity(s).

osi-modelApplication Attacks exploit a weakness in the Layer 7 or as the name suggests the application layer.

The cyber community, in general, agrees that application attacks are both the most sophisticated and the most challenging to identify and/or mitigate.

Application attacks begin with making a connection with the host then it exhausts the dnshost’s resources by controlling processes and transactions. DNS Flood attacks are the most well known.

DNS floods are a symmetrical attack that endeavors to exhaust server-side assets like memory or CPU, with an inundation of UDP requests, generated by malicious scripts running on multiple botnet machines. The criminals will often target one or more DNS servers belonging to a specified zone, with the goal of obstructing and overwhelming the resolution of resource records of that zone and its subzones.

Protocol attacks specifically exploit weaknesses in the Layer 3 and Layer 4 protocol stack by consuming all the processing capacity of the intermediate critical resources like a firewall causing service disruption; With the most notorious attack being the Ping of Death.

A ‘ping’ is part of the Internet Control Message Protocol (ICMP) which is a networking utility that determines whether or not a host is reachable. The ICMP request packet is sent to the host, which the host then responds with an ‘echo’ reply. The size of an accurately formed ICMP request packet should be no larger than 65,535 bytes; anything larger is in violation of the Internet of death

Criminals, in turn, send malformed packets in fragments as fast as possible in which the host attempts to assemble using up bandwidth. This leads to a packet size which violates the internet protocol of 65,535 bytes causing a buffer overflow, and eventually causing the host to crash and become unavailable for legitimate users. This is a Ping of Death DDoS attack.

DDoS scripts are written most often in Python, PHP, or Pearl and refers to malicious software that enables the execution of DDoS attacks.Each script can diverge in severity, ease of use and impact and attacks at the application layer.

Some of the DDoS scripts available for free on the internet (too many to list) include

LOIC  (Low Orbit In Canon)

LOIC was made famous by the hacker group Anonymous. It is easy to use especially for beginners, because of its easy-to-use GUI; all you need is the URL of the IP address of the server. LOIC performs the DOS by sending UDP, TCP, or HTTP requests to the victim server.


XOIC comes with an easy-to-use GUI, so all levels can easily use it to perform attacks on servers and websites anonymously and secretly. All that is required is an IP address.

XOIC has three methods including, Test mode; Attack mode; Attack mode with a TCP/HTTP/UDP/ICMP Message.


Tors Hammer is written in Python, and it is a slow post tool* that can be run through the TOR network** and can kill most unprotected web servers running Apache and IIS by means of a single occurrence.

HOIC (High Orbit in Cannon)

HOIC is written in BASIC and is an open source network stresser that can attack as many as 256 URLs at any one time.


Slowloris is written in Python and operates at the application layer. It opens as many connections to the web server as it can, and holds them open as long as possible by sending partial requests, and periodically adding them to keep the connection alive but never completing and denying connection attempts from legitimate users.

DDoS toolkits are software packages that require greater resources and generally more in-depth knowledge of scripting and systems and attacks the network layer. They infect computers and other Internet-connected devices (IoT) with malware in order to build a botnet.

The malicious bot landscape continues to evolve. Considering that more than 60 percent of the Internet traffic is generated by bots of which upwards of 30 percent is represented by malicious bots which present a force to be reckoned with when talking about internet security.

DDoS attacks can be unassuming or sophisticated, regardless, they are always ddos ransomdangerous, calculated and profit-driven with DDoS ransom being one of the nastiest elements.

Extortionists will demonstrate their capabilities by acting out an attack such as shutting down a website, followed by a threatening e-mail requesting a monetary sum usually in Bitcoin to be paid within a time-period. ‘Pay the ransom or face greater attacks.’

The extortionists will continue broadening their scope and diversifying their targets to include more diverse industry sectors and larger organizations and even larger payoffs.

Below find a few strategies which can make your network less vulnerable to attackers, remembering, there is No 100 Percent Solution to prevent cyberattacks. Continuous learning and continuous experimentation are critical.

  • Limit the number of new connections. Set parameters for the number of new connections during specific periods of time by a single user or by the network. Doing this simple strategy will make it that much harder for a criminal to overload systems.
  • Bandwidth Shaping. If configured correctly, bandwidth shaping can be an easy to apply policy against DDoS attackers.
  • Network Segmentation. By dividing your network into segments into public and internal sections, each protected by a firewall, this tactic can support your internal network when there is a DDoS attack against your public-facing systems.

CyberSecurity is a shared responsibility. Stop. Think. Connect.

Security Is An Arms Race, The Only Way To Win, Is To Stay Ahead And Stay Knowledgeable.


Securing your home wireless network is not a game, it is a serious business. If your network is not secured, an online cybercriminal will exploit it; it is just a matter of time. They will ‘listen’ to your traffic, retrieve sensitive data and/or take advantage of your network to launch malicious attacks. For this reason, learning how to exploit your home network before the cybercriminal does, is a very smart move.

Quick Overview On Wireless Security Options

  • Wired Equivalence Privacy
  • First 802.11 standard.
  • Very easily ‘hacked’ due to a 24 Bit Initialization Vector (IV) and weak encryption.
  • Uses RC4 Stream Cipher and 64 or 128 Bit keys.

Never use.

[A cyber attack executed against retailer T.J. Maxx in 2009 was traced back to WEP vulnerabilities.]


  • Wired Equivalence Privacy.
  • Implemented to address major WEP flaws.
  • Backwards compatible with WEP.
  • Personal and Enterprise Mode.
  • RC4 along with longer IV’s 256 Bit Keys.
  • Each user acquires new keys with TKIP.
  • Enterprise mode uses 802.1x & EAP

Only use if WPA2 is not available.


  • Wired Equivalence Privacy.
  • Strongest standard.
  • Additionally, the Advanced Encryption does not affect performance.
  • Personal and Enterprise mode.
  • Replace both RC4 and TKIP with CCMP and AES algorithm for a strong authentication and encryption
  • Seamless roaming. Individuals can move from one AP to another on the same network without having to reauthenticate.

Most secure method.

There are fundamentally two types of vulnerabilities which can be found in the Wireless Home Network.  The most common one is poorly constructed configuration including weak passwords, no security settings, or using the ‘out of the box’ default configurations.

  • First things first, change the name of your Wi-Fi network, also known as the SSID (Service Set Identifier).
  • Your wireless router comes pre-set with a default password. That is very easy for a cybercriminal to guess it, especially if they can learn the manufacturer.
  • A strong password should be at least 8 characters and should include uppercase, lowercase, and special characters – like @#?%^&*.
  • Adding just one capital letter, and one special character changes the processing time for an 8 character password from 2.4 days to 2.10 centuries. Think about that!


  • The second vulnerability is using weak encryption including the security keys (WEP, WPA) to protect the wireless network.
  • The strongest encryption settings to increase your Wi-Fi protection is WPA2 AES.
    • AES is short for Advanced Encryption Standard and is used by governments around the world, including the US.
  • WPA2 AES is a standard security system now, so the majority of wireless networks should be compatible with it.
  • If you are using WPA2 personal. Disable WPS.
    • WPS stands for Wi-Fi Protected Set-up.  It is a wireless networking standard that makes connecting a router and wireless devices faster and easier. However, although WPS can make your life easier, it is very vulnerable to attacks. (See Fern Wi-Fi)

Quick Overview On Wireless Cracking and the Tools

Knowledge is powerful. Cybercriminals are powerful because they have the critical knowledge that leverages all other knowledge, the ability to solve that puzzle-known as your password and win that prize-known as your data. Beat them to the finish line.


If you enjoy networking and know your protocols, then you will so enjoy Wireshark as much as I do. Essentially, it is a network protocol analyzer tool. You can ‘live capture packets’ and analyze them in order to find various things related to your network and lets you see what’s happening at a microscopic level. This tool is available for Linux, Windows, OS X, Solaris and other platforms.


This is one of the most widely-known, and many would say popular wireless password cracking tools.

Aircrack-ng is a complete suite of tools to assess your Wi-Fi network security. It focuses on different areas of WiFi security:

  • Monitoring: Packet capture and export of data to text files for further processing by third party tools.
  • Attacking: Replay attacks, deauthentication, fake access points and others via packet injection.
  • Testing: Checking Wi-Fi cards and driver capabilities (capture and injection).
  • Cracking: WEP and WPA-PSK (WPA 1 and 2).

All tools are command line which allows for heavy scripting.  It works primarily on Linux but also Windows, OS X, NetBSD, as well as Solaris and even eComStation 2.


Another popular wireless LAN password cracking tool and it can crack WEP keys of a Wi-Fi802.11b network. This tool passively monitors transmissions and then computes the encryption key when enough packets have been gathered. This tool works on Linux and Windows platform.


This is yet another popular Wi-Fi 802.11 a/b/g/n layer 2 wireless network sniffer and intrusion detection system. It is available for Windows, Linux, OS X and other platforms. This tool is used in Wi-Fi troubleshooting and passively collects packets to identify the standard network and also detects the hidden networks. Built on a client-server modular architecture, this tool can sniff 802.11b, 802.11a, 802.11g, and 802.11n traffic.

Fern Wi-Fi

Fern Wi-Fi Wireless Cracker helps with network security by allowing you to see real-time network traffic and can identify hosts. It works with Apple, Windows and Linux platforms. It can run other network based attacks on wireless or Ethernet based networks. For WPA/WPA2, it uses WPS based on dictionary based attacks. For WEP, it uses Fragmentation, Chop-Chop, Caffe-Latte, ARP Request Replay or WPS attack.


inSSIDer is the only tool that I use in which I pay for (19.99), But it is worth it. It is a very popular Wi-Fi scanner for both Microsoft Windows and OS X platforms. The Wi-Fi scanner can find open Wi-Fi access points, track signal strength, and save logs with GPS records. One of the best uses is to find issues in wireless networks. That alone is worth the money!

I learned how to use these tools through trial and error. My first target was my wireless home network, and I kept at it until I was able to strengthen my overall security. Then I focused on my family and friends (with their permission). Breaking into a wireless network without permission to gain access is a cyber-crime. Do not put yourself at risk.

I was able to turn this experience into an educational session for both my ‘test group’ and me. I was able to show them the importance of having a strong wireless network, and I proved to myself that I could ‘hack’ them.

Overall Results – 8 home wireless networks tested (Again, I stress, I had their permission)

  • 5 Set up their networks straight out of the box security – Fail
  • 1 Networks used WEP  – Fail
  • 1 Network had WPS enabled – Fail
  • 1 Network used a well-known password (hello…Not kidding) – Fail

Cybersecurity is a shared responsibility. Stop. Think. Connect.