SecurityBrief Asia logo
Asia's leading source of cybersecurity and cyber-attack news
Story image

Botnets are being overshadowed by ransomware - in the media, at least

Mon 12 Jun 2017
FYI, this story is more than a year old

Recently, the much-reported WannaCryptor ransomware attack took the media by storm, receiving considerably more coverage than might have been expected for this type of malware, and overshadowing other internet threats at the same time.

More dangerous than ransomware, however, is malware capable of taking complete control over affected machines. This malware enables the control of affected machines en masse; in this case, the network of such machines is called a botnet.

The reason that botnets pose a bigger threat to the internet than ransomware is that their operators are capable of using them to execute virtually any task with a success rate of close to 100%. It’s true, botnets are not as visible as ransomware, and, for the general public, they fly under the radar – but that can change at any given moment.

Botnets not only harm the owners of infected computers, but others too – they can send out spam, distributing a range of scams or even ransomware; perform so-called DDoS attacks; or be used to cheat advertising networks. Each of these is concerning, as spam forms 50%-70% of all email traffic. (Amongst those with malicious attachments, 85% can be linked to ransomware.) 

From the point of view of an owner with an infected computer, the botnet operator can try to break into the victim’s bank account or harvest other credentials (e.g. for social media or email accounts) or at least utilize the system’s resources for Bitcoin mining. Furthermore, a botnet’s ultimate and underestimated threat is that the operators can easily encrypt every single computer in their botnet.

Recent development in botnets

Within the overall maturation of cybercrime, botnet operators are seeking the best margins from the computers under their control. Originally, their primary means of monetization was spam distribution. Potent botnets can send billions of spam emails per day – reportedly, the record holder is the Marina botnet with a spam capacity of a staggering 90 billion plus emails.

The biggest botnets in history were too large to evade the attention of authorities and security firms who have carried many operations against botnets and eventually dismantled some of them.

To avoid detection and improve resiliency, botnet architects innovate. They’ve abandon the simplest client-server model and have switched to the P2P (Peer-to-Peer) model where bots perform as both server and client, i.e. they both send and receive commands, thus avoiding having a single point of failure.

As recently as December 2016, a botnet called Avalanche was taken down in a coordinated effort between authorities and security firms, among them ESET. Avalanche’s infrastructure was sophisticated and very resilient. It employed so-called double fast-flux technology, which frequently changes both the IP addresses of the C&C servers and the name servers.

To take down the botnet, 800,000 web domain addresses were seized, blocked or sinkholed, 220 servers were taken offline and five people were arrested. Avalanche had potentially more than a million victims – half a million of them were identified and eventually notified by their ISPs. Avalanche distributed many different types of malware (a clear indicator that this fast-flux network was sold as a service to other cybercriminals), mostly credential stealers, ransomware and banking trojans.

Botnets: not just personal computers

While typical botnets comprise personal computers, two other types of bots exist: servers and “things”. Each of them have different advantages for the criminals.

Infected webservers may redirect traffic and, due to them typically being more powerful than personal computers, as well as their tendency to sit on faster internet lanes, are suitable for spam distribution.

Devices that fall under the Internet of Things (IoT) category tend to be poorly secured and thus easily infected with malware. Due to their nature, “things” can be used for the simplest of tasks – their use being limited to DDoS attacks. However, this issue is huge, as according to Gartner, a leading IT research and advisory company, the number of connected “things” will reach 20.8 billion by 2020.

Enslaved servers

One of the biggest server botnets in history was dismantled by the coordinated action of law enforcement agencies from several countries with support from ESET in 2014. In this case, the so-called Operation Windigo led to the vivisection of a large botnet based on the Linux/Ebury OpenSSH backdoor.

ESET’s analysis found that over 25,000 servers were affected in the two years prior to the operation, and more than 10,000 of them were still infected on the date of the takedown. Infected servers were used to redirect half a million-web visitors daily to malicious content and were able to send more than 35 million spam messages per day.

Mumblehard was another server botnet successfully taken down based on ESET’s expertise. An analysis of the sinkholed C&C server’s traffic showed that the botnet consisted of around 4,000 infected servers, used for sending spam. To this end, the gang behind Mumblehard utilized a script that automatically monitored one of the leading blacklists, the Spamhaus Composite Blocking List for IP addresses of all spam-bots.

If one of its IP addresses was found to be blacklisted, the script requested the delisting of the IP address. Such requests are protected with a CAPTCHA to avoid automation, but OCR (Optical character recognition), or an external service if OCR didn’t work, was used to break the protection.

Enslaved “things”

So-called IoT botnets came to prominence in October 2016 when the Domain Name System (DNS) service provider Dyn was the target of a sustained DDoS attack. This led to outages at major sites and services, including Twitter, SoundCloud, Spotify, and many others. In the intervening month, as data on the Mirai Botnet used in the attack emerged, the botnet reappeared in attacks on the Krebs on Security website, reaching speeds of 620 Gbit/s, and later a record-setting 1 Tbit/s attack on a web hosting provider, OVH.

Mirai is a network of online consumer devices such as IP cameras and home routers infected with the Mirai malware. The malware scans the internet for vulnerable devices, i.e. those running outdated versions of Linux and having default settings including factory pre-set credentials. Any such device gets infected and becomes part of the botnet, checking the C&C server for commands, i.e. the IP address to attack with coordinated traffic.

Unfortunately, the source code for Mirai was published in hacker forums as open-source which has enabled the wider application of this technique to other malware projects. Thus any unsecured IoT device – ESET research suggests at least 15% of home routers, estimated to be 105 million globally, are unsecure and at high risk of being infected by Mirai-like malware and taking part in IoT DDoS attacks.

With DDoS attacks on the rise (whether the botnets involved comprise personal computers, servers or “things”) organizations should take steps to get ready, not only technically, but because there are also significant legal implications.

Necurs: An example to follow closely Necurs, the world’s largest spam botnet with nearly five million infected bots, of which one million are active each day, has added a new module that can be used to launch DDoS attacks. The module was added in 2016, but was only recently spotted by security researchers and investigated.

Should the Necurs botnet operators really launch a full-size DDoS attack, it would be by far the biggest one ever. However, this news hasn’t raised much attention. Why?

Necurs was a stable part of the spam scene and considered a global leader in ransomware distribution. However, since December 2016, Necurs has jumped into another type of cybercrime when it started to distribute financial stock-scam emails with fake news on selected stocks. These were used to inflate the price of the targeted stocks and then cash in on them later.

Evolving from ransomware to the stock-scam and on to DDoS over the course of a few months – the speed at which the Necurs operators change their botnet’s utilization illustrates that there are dramatic developments on the botnet scene. With the exception of the DDoS capability, all the currently deployed botnet business models bet on long-term sustainability.

Understandably, setting the botnet up is the hardest part of the criminals’ efforts and the very last thing they need is to attract the attention of the authorities, risk having their servers sinkholed or even seized, and ultimately finding themselves in jail. Apparently, large botnet operators’ focus on sustainability actually prevents them from taking part in spectacular DDoS attacks.

However, should they – for whatever reason – opt for a big bang, we could expect something exceptional. Hopefully, it would only be a record-breaking DDoS attack or, worse still, a ransomware attack – this time encrypting the bots themselves instead of merely distributing emails with infected attachments.

Underestimated threat: Whole botnets held ransom

These threats support the claim that botnets are more dangerous than the ransomware campaigns that the internet has suffered so far. Compare the scale: the latest major ransomware outbreak, WannaCryptor, also known as WannaCry, affected some 350,000 computers.

Botnets overall contain hundreds of millions computers (according to the FBI, approximately 500 million computers are infected globally each year). Not only that, but each and every one of them could become encrypted by ransomware. Not to mention that if the operators one day decide to do so, they could simply distribute a ransomware payload of their choice.

It would be as easy as providing the botnet with a new set of instructions to distribute spam or use it to attack a number of targets with a flood of requests. In another words, an operation to encrypt all active computers in a botnet would likely reach a 100% success rate, with nothing to stand in its way.

Botnet protection: A needed solution Even without the ultimate threat of encrypting all the bots, botnets are a clear threat and present danger. Thus, both consumers and organizations should work to avoid falling victim to botnet malware.

Sure, the ultimate goal is to prevent any malware from crossing the perimeter or from executing its malicious tasks or – at the very last line of defense – containing the damage. To achieve this goal, a full range of security tools and methods should be deployed – from security training to implementing endpoint and network security solutions to data protection and backup/recovery solutions. As for protection from botnets and preventing falling victim to this kind of attack, a specialized layer of protection should be deployed.

Leading vendors – amongst them ESET – offer Botnet Protection as an additional security layer, to detect malicious or suspicious communications used by botnets. Any such communication is then blocked and reported to the user. Ransomware is a pretty visible and painful issue; however, botnets pose a hidden threat – which, if it were ever to materialize, are quite capable of paralyzing the internet.

Article by Welivesecurity/ESET.

Related stories
Top stories
Story image
Cybersecurity
Cybersecurity prompts upgrade for 1.3 billion electricity meters
ABI Research finds Advanced Metering Infrastructure (AMI) and cybersecurity concerns are prompting the upgrade of 1.3 billion electricity meters by 2027.
Story image
Training
Trojan cyber attacks hitting SMBs harder than ever - Kaspersky
In 2022 the number of Trojan-PSW detections increased by almost a quarter compared to the same period in 2021 to reach 4,003,323.
Story image
New Relic
New Relic launches vulnerability management platform
New Relic has introduced New Relic Vulnerability Management to help organisations find and address security risks faster and with greater precision.
Story image
Employment
Tech job moves - Forcepoint, Malwarebytes, SolarWinds & VMware
We round up all job appointments from May 13-20, 2022, in one place to keep you updated with the latest from across the tech industries.
Story image
BeyondTrust
BeyondTrust integrates Password Safe solution with SailPoint
BeyondTrust has announced the integration of BeyondTrust Password Safe with SailPoint identity security offerings.
Story image
Data Protection
Barracuda launches new capabilities for API Protection
"Every business needs this type of critical protection against API vulnerabilities and automated bot attacks," Barracuda says.
Story image
Nozomi Networks
Nozomi Networks, Siemens reveal software integration
Nozomi Networks and Siemens have extended their partnership by embedding Nozomi Networks’ software into the Siemens Scalance LPE local processing engine.
Story image
ChildFund
ChildFund launches new campaign to protect children online
ChildFund says WEB Safe & Wise aims to protect children from sexual exploitation and abuse online while also empowering them to become digitally savvy. 
Story image
Migration
Let’s clear the cloud visibility haze with app awareness
Increasingly, organisations are heading for the cloud, initiating new born-in-the-cloud architectures and migrating existing applications via ‘lift and shift’ or refactoring.
Story image
Silver Peak
The path to an adaptive, modern network
Managing and securing the network looks different than it did just two years ago—especially given that most of these networks are made up of multi-generations of infrastructure stitched together over time.
Story image
Ivanti
Ivanti and Lookout bring zero trust security to hybrid work
Ivanti and Lookout have joined forces to help organisations accelerate cloud adoption and mature their zero trust security posture in the everywhere workplace.
Story image
Malware
New vulnerabilities found in Nuspire’s Q1 2022 Threat Report
“Threat actors are quickly adjusting their tactics and these exploits tend to get industry attention, but the threat posed by older and attacks still persists."
Story image
Cybersecurity
The 'A-B-C' of effective application security
Software applications have been a key tool for businesses for decades, but the way they are designed and operated has changed during the past few years.
Story image
Tech job moves
Tech job moves - Datacom, Micro Focus, SnapLogic and VMware
We round up all job appointments from May 6-12, 2022, in one place to keep you updated with the latest from across the tech industries.
Story image
Artificial Intelligence
How to ensure ethical deployment of AI implementations
The increase in automation and machine technology such as AI and machine learning has unlocked a whole new level of scale and service to organisations. 
Story image
Artificial Intelligence
Updates from Google Workspace set to ease hybrid working troubles
Google Workspace has announced a variety of new features which will utilise Google AI capabilities to help make hybrid working situations more efficient and effective.
Story image
Application Security
What are the DDoS attack trend predictions for 2022?
Mitigation and recovery are vital to ensuring brand reputation remains solid in the face of a Distributed Denial of Service (DDoS) attack and that business growth and innovation can continue.
Story image
Cybersecurity
ThoughtLab reveals 10 best practices for cybersecurity in 2022
The benchmarking study reveals best practices that can reduce the probability of a material breach and the time it takes to find and respond to those that happen.
SonicWall
Find out how you and your business can prevent being caught out by everything from ransomware to cryptojacking.
Link image
Story image
Ransomware
Zerto unveils updates to ransomware recovery capabilities
"Organisations face increased risks from the volume and sophistication of ransomware attacks prevalent today."
Story image
DDoS
NT selects Radware to improve telecom cyber defenses
National Telecom Public Company (NT) has chosen Radware to strengthen the cyber defences of its international telecommunications infrastructure.
Story image
Ransomware
Ransomware hits 65% of organisations in Singapore
Next-generation cybersecurity firm Sophos has released its annual survey and review of real-world ransomware experiences in the State of Ransomware 2022.
Story image
Customer experience
Gartner recognises Okta for abilities in Access Management
Okta has announced it has been recognised as a Customers' Choice for the fourth time in a row in the Gartner Peer Insights "Voice of the Customer" report.
Story image
Artificial Intelligence
ForgeRock releases Autonomous Access solution powered by AI
ForgeRock has officially introduced ForgeRock Autonomous Access, a new solution that uses AI to prevent identity-based cyber attacks and fraud.
Story image
Cybersecurity
Hard numbers: Why ambiguity in cybersecurity no longer adds up
As cybersecurity costs and risks continue to escalate, CEOs continue to struggle with what their investment in cyber protection buys. Getting rid of ambiguity becomes necessary.
Story image
Apricorn
Data backup plans inadequate, data still at risk - study
The Apricorn 2022 Global IT Security Survey revealed that while the majority organisations have data backup plans in place, data for many are at risk.
Story image
Cybersecurity
Managed service providers: effective scoping to avoid costly vendor pitfalls
Managed security services are outsourced services focusing on the security and resilience of business networks.
Story image
Remote Working
Successful digital transformation in the hybrid work era is about embracing shifting goalposts
As organisations embraced remote working, many discovered they lacked the infrastructure needed to support history’s first global load test of remote work capabilities.
Story image
Supply chain
Jetstack promotes better security with supply chain toolkit
The web-based resource is designed to help organisations evaluate and plan the crucial steps they need to establish effective software supply chain security.
Story image
Workato
Workato unveils enhancements to enterprise automation platform
"The extra layer of protection with EKM, zero-logging, and hourly key rotation gives customers a lot more visibility and control over more sensitive data."
Story image
Sift
Sift shares crucial advice for preventing serious ATO breaches
Are you or your business struggling with Account Takeover Fraud (ATO)? One of the latest ebooks from Sift can provide readers with the tools and expertise to help launch them into the new era of account security.
Story image
Remote Working
How zero trust and SD-WANs can support productive remote working
The way people connect with applications and data has changed, users are remotely accessing resources that could be stored anywhere from a corporate data center to the cloud.
Story image
Ransomware
A third of companies paying ransom don’t recover data - report
Veeam's report finds 76% of businesses who are victims of cyberattacks paid the ransom to recover data, but a third were still unable to get their information back.
Story image
Cybersecurity
A10 Networks finds over 15 million DDoS weapons in 2021
A10 Networks notes that in the 2H 2021 reporting period, its security research team tracked more than 15.4 million Distributed Denial-of-Service (DDoS) weapons.
Story image
Cybersecurity
Video: 10 Minute IT Jams - An update from IronNet
Michael Ehrlich joins us today to discuss the history of IronNet and the crucial role the company plays in the cyber defence space.
Story image
Digital Transformation
How to modernise legacy apps without compromising security
At a time when digital transformation has become central to business, even the most important applications come with a ‘use-by’ date.
Story image
Artificial Intelligence
AI-based email security platform Abnormal Security valued at $4B
"A new breed of cybersecurity solutions that leverage AI is required to change the game and stop the rising threat of sophisticated and targeted email attacks."
Story image
Ransomware
Cybersecurity starts with education
In 2021, 80% of Australian organisations responding to the Sophos State of Ransomware study reported being hit by ransomware. 
Story image
Cybersecurity
CyberArk launches $30M investment fund to advance security
CyberArk has announced the launch of CyberArk Ventures, a $30 million global investment fund dedicated to advancing the next generation of security disruptors.
Story image
Cybersecurity
More than 40% of banks worried about cloud security - report
Publicis Sapient's new report finds security and the lack of cloud skills and internal understanding of business benefits are big obstacles for banks moving to the cloud.
Story image
Cybersecurity
Noname Security partners with Netpoleon to target API issues
Specialist API security firm Noname Security has appointed Netpoleon as its distributor in Australia and New Zealand.
Story image
Cloud Security
Aqua Security createa unified scanner for cloud native security
“By integrating more cloud native scanning targets into Trivy, such as Kubernetes, we are simplifying cloud native security."
Story image
VPN
Palo Alto Networks says ZTNA 1.0 not secure enough
Palo Alto Networks is urging the industry to move to Zero Trust Network Access 2.0 because previous versions have major gaps in security protection.
Story image
SaaS
Rubrik Security Cloud marks 'next frontier' in cybersecurity
"The next frontier in cybersecurity pairs the investments in infrastructure security with data security giving companies security from the point of data."