December 2020 - Appunti dalla rete

Top 10 Dangerous DNS Attacks Types and The Prevention Measures

From the above topic, we can guess that today, we are going to discuss the top 10 DNS attacks and how to mitigate them. DNS stands for Domain Name System which remains under constant attacks, and thus we can assume there is no end in sight because the threats are growing increasingly nowadays.

DNS generally uses UDP fundamentally and in some cases, uses TCP as well. When it uses the UDP protocol, which is connectionless and can be tricked easily.

Thus DNS protocol is remarkably popular as a DDoS tool, and DNS, recognized as the internet’s phonebook, which is a component of the global internet foundation that transmutes between well-known names and the number that a computer needed to enter a website and send an email.

DNS has long been the target of attackers looking to take all custom of corporate and secret data, hence, the warnings in the past year indicate a worsening of the condition.

As per the IDC’s research, the average costs correlated with a DNS mugging rose by 49% associated with a year earlier. However, in the U.S., the average price of a DNS attack trims out at more than $1.27 million.

Approximately half of the respondents (48%) state that wasting more than $500,000 to a DNS attack, and about 10% say that they lost more than $5 million on each break. In extension, the preponderance of U.S. companies says that it needed more than one day to determine a DNS attack.

Shockingly, as per the information both in-house and cloud applications were destroyed, the 100% growth of threats in the in-house application interlude, frothingly it is now the most widespread destruction experienced that IDC composed.

Thus the “DNS attacks are running away from real brute-force to more complicated attacks running from the internal network. Thus the complicated attack will push the organizations to use intelligent mitigation tools so that they can easily cope with insider threats.”

Therefore we have provided the top 10 DNS attacks and the proper solutions to fix them, so that it will be easy for the organizations to recognize the attacks and can quickly solve it.

Famous DNS Attacks Type:

DNS Cache Poisoning Attack
Distributed Reflection Denial of Service (DRDoS)
DNS Hijacking
Phantom Domain Attack
TCP SYN Floods
Random Subdomain Attack
DNS Tunneling
DNS Flood Attack
Domain Hijacking
Botnet-based Attacks

DNS Cache Poisoning Attack

At first, we have the cache poisoning, it’s one of the frequent attacks, and its main aim is to take the web users towards the scam websites, as for example, a user accesses gmail.com through the web browser to consult their mailbox.

Moreover, the DNS is becoming poisoned, and it’s not the gmail.com page which is exposed but a scam page determined by the criminal, in order, for example, to reclaim the email box accesses. Thus the users accessing the correct domain name will not see that the website they’re entering is not the right one but a scam one.

Basically, it generates an excellent possibility for cybercriminals to use phishing techniques to steal information, both identification information or credit card information from ingenuous victims. The attack can be devastating, depending on several factors, the attacker’s purpose, and the DNS poisoning impact.

DNS Attack Mitigation – Cache poisoning

As per the information, there are several forms to solve or to prevent this attack. For beginners, the IT teams should configure DNS servers to rely as small as possible on trust relations with other DNS servers. Performing so will make it more difficult for attackers to practice their DNS servers to debased their targets’ servers. There is another method to prevent cache poisoning attacks, as IT teams should also configure their DNS name servers to:-

To restrict recursive queries.
To store only data associated with the requested domain.
To restrict query responses to only given information about the demanded domain.

Not only this, but there are also some cache poisoning tools accessible to help organizations for preventing cache poisoning outbreaks. And the most famous cache poisoning prevention tool is the DNSSEC (Domain Name System Security Extension), a tool that is produced by the Internet Engineering Task Force, which provides reliable DNS data authentication.

Distributed Reflection Denial of Service (DRDoS)

Distributed reflective denial of service (DRDoS) attacks concentrate on bringing down the availability of an asset within an authoritative volume of UDP acknowledgments. In some instances, the attacker would transfer a DNS, NTP, etc.

They demand a parodied source IP, with the purpose of a more extensive acknowledgment being transferred to the host who indeed continues at the address that was forged.

UDP is the protocol of different choices for this variety of attacks, as it does not build a connection state. For example, suppose a spoofed source of IP in the SYN package of a TCP connection would cause immediate termination just because the SYN/ACK will go away.

This practice makes reflection potential and possible, meanwhile, regulating these attacks at the proper scale, the idea of shared reflection becomes clear; hence, various endpoints transmitting spoofed UDP offers, generating acknowledgments that will be concentrated upon a target.

Once these response packs begin to appear, the goal experiences a loss of availability.

How to Prevent?

Usually, organizations should commence on preparing for DDoS attacks in advance, it is exceedingly harder to answer after an attack because it is already underway.

Moreover, DDoS attacks can’t be stopped, therefore some steps can be taken to make it more troublesome for an attacker to perform a network unresponsive. The following steps will help you to scatter organizational assets to bypass performing a single deep target to an attacker.

First, locate servers in different data centers.
Assure that your data centers are located on various networks.
Make sure that data centers have several paths.
Make sure that the data centers, or the networks that the data centers are related to, have no essential security holes or single points of failure.

An organization that relies on servers and Internet port, for them, it is essential to make sure that devices are geographically scattered and not located in a particular data center.

Moreover, if the resources are already geographically dispersed, then it’s essential to inspect each data station is having more than one channel to the internet and assure that not all data stations are attached to the corresponding internet provider.

DNS Hijacking

DNS hijacking is a method in which an individual can divert to the doubtful DNS (Domain Name System). However, it may be achieved by using malicious software or unauthorized alteration of a server.

Meanwhile, the individual has the authority of the DNS; they can guide others who obtain it to a web page that seems identical but carries extra content like advertisements. They can also guide users to pages carrying malware or a third-party search engine as well.

How to Prevent?

A DNS name server is a compassionate foundation that needs necessary protection measures because it can be hijacked and used by several hackers to raise DDoS attacks on others, thus, here we have mentioned some prevention of DNS hijacking.

See for resolvers on your network.
Critically restrict access to a name server.
Utilize measures against cache poisoning.
Instantly patch known vulnerabilities.
Separate the authoritative name server from the resolver.
Restrain zone alterations.

Phantom domain attack

Phantom domain attacks are kind of comparable to casual subdomain attacks. Thus in this kind of attack, the attackers attack your DNS resolver and overpower it to use up supplies to determine that’s what we name “phantom” domains, as these phantom domains will never respond to the queries.

The main motive of this attack is to let the DNS resolver server await for the answer for a long time, ultimately leading to failure or deteriorated DNS performance problems.

How to Prevent?

To identify phantom domain attacks, you can analyze your log messages. Moreover, you can also follow the steps that we have mentioned below to mitigate this attack.

First, increase the number of recursive clients.
Use a proper sequence of the following parameters to gain optimum results.
Restrict recursive queries per server and Restrict recursive inquiries per zone.
Empower to hold down for non-responsive servers and Check recursive queries per zone.

When you allow any of the options, the failure values are set at an excellent level for overall operations. However, you should keep the default charges while using these commands, moreover, it guarantees that you know the consequences if you want to replace the default values.

TCP SYN Floods

An SYN Flood is a simple form of Denial-of-Service (DDoS) attack that can target any operation related to the internet and thus implementing Transmission Control Protocol (TCP) services.

An SYN wave is a type of TCP State-Exhaustion attack that endeavors to utilize the connection element tables present in common infrastructure elements, for example, load balancers, firewalls, Intrusion Prevention Systems (IPS), and the utilization servers themselves.

Hence, This type of attack can bring down even high-capacity devices fitted to managing millions of links. Moreover, a TCP SYN flood attack occurs when the attacker overflows the system with SYN questions to destroy the target and make it incapable of reacting to new real connection offers.

Thus it encourages all of the target server’s information ports into a half-open state.

How to Prevent?

So, the firewalls and IPS devices, while important to network security, are not sufficient to protect a network from complex DDoS attacks.

Nowadays, the more sophisticated attack methodologies demand a multi-faceted program that allows users to look beyond both internet foundation and network availability.

Thus there are some capabilities that you can count for more powerful DDoS security and faster mitigation of TCP SYN flood attacks.

At first, provide proper support to both inline and out-of-band deployment to assure that there is not only one single point of collapse on the network.
Extensive network distinctness with the capacity to see and examine traffic from various parts of the network.
Different sources of threat intelligence, including statistical exception detection, customizable entrance alerts, and fingerprints of known threats that assure fast and reliable detection.

Extensible to handle attacks of all sizes, extending from low-end to high-end and high-end to low-end.

Random Subdomain Attack

This is not the most prevalent type of DNS attack, but it can happen from time to time on several networks. Hence, the random subdomain attacks can often be identified as DoS attacks, as their creation adheres to the same goal as simple DoS.

Incase, spoilers send a lot of DNS inquiries against a healthy and active domain name. However, the questions will not target the primary domain name, but it will harm a lot of non-existing subdomains.

Basically, the main motive of this attack is to build a DoS that will immerse the authorized DNS server that receives the primary domain name, and finally let the interruption of all DNS record lookups.

Thus It’s an attack that’s hard to identify, as the queries will come from infected users who don’t even understand they’re sending certain types of questions, from what are eventually legitimate computers.

How to Prevent?

Thus we have provided you a simple method for preventing the random subdomain attack only in a 30-minute.

In the beginning, you have to learn the techniques to mitigate the attacks that generate extreme traffic on resolvers and web resources that are connected with the victim the names that can be taken down.
Next, Hear about modern capabilities like Response Rate Limiting for preserving DNS experts that provoke attacks.

DNS tunneling

This is a cyber attack that is used to carry encoded data from different applications inside DNS acknowledgments and queries.

Meanwhile, this system wasn’t formerly created to attack multitudes, but to bypass interface controls, now it is mostly used to achieve remote attacks.

To implement DNS tunneling, attackers demand to gain entrance to a settled system, as well as access to an internal DNS server, a domain name, and a DNS authoritative server.

How to Prevent?

To configure the firewall to identify and block DNS tunneling by designing an application rule that uses some protocol object, we have mentioned three steps to mitigate these types of attacks.

Create an access rule.
Create a protocol object.
Create an application rule.

DNS Flood Attack

This is one of the most primary types of DNS attacks, and in this Distributed Denial of Service (DDoS), the intruder will hit your DNS servers.

The main motive of this kind of DNS flood is to completely overload your server so that it cannot maintain serving DNS requests because all the treated DNS zones influence the purpose of resource records.

Thus this kind of attack is relieved easily as the source usually comes from one single IP. However, it can get complicated when it becomes a DDoS where a hundred or thousand gatherings are involved.

While a lot of questions will be immediately identified as malicious bugs and a lot of legitimate requests will be made to mislead defense devices, hence, this makes the mitigation method a little bit difficult sometimes.

How to Prevent?

Domain Name System (DNS) has developed a target of the Distributed Denial of Service (DDoS) attacks. When a DNS is below a DDoS flood attack, all the domain data under that DNS enhances unreachable, thus ultimately creating the unavailability of those appropriate domain names.

Hence, for this type of attack, we have introduced a method that includes the periodic stale content update and manages a list of the most commonly queried domain names of several DNS servers. Hence our simulation outcomes show that our method can work more than 70% of the total cache replies during a massive DNS Flood attack.

Domain Hijacking

This type of attack involves settings in your DNS servers and domain registrar that can manage your traffic away from the actual servers to new destinations.

Domain hijacking is usually affected by a lot of determinants related to exploiting a vulnerability in the domain name registrar’s system, but can also be performed at the DNS level when attackers take command of your DNS records.

Hence when the attacker hijacked your domain name, it will be used to originate malicious movements such as installing up a fake page of repayment systems like PayPal, Visa, or bank systems. Attackers will produce an identical copy of the real website that reads critical personal knowledge, such as email addresses, usernames, and passwords.

How to Prevent?

Thus you can simply mitigate the domain hijacking by practicing a few steps that we have mentioned below.

Upgrade your DNS in the application foundation.
Use DNSSEC.
Secure access.
Client lock.

Botnet-based Attacks

If we talk about the botnet, then let me clarify that it is a number of Internet-connected devices, and it can be practiced to implement a distributed denial-of-service attack (DDoS attack), which steal data, transmit spam, and enables the attacker to obtain access to the device and its connection.

Moreover, botnets are diverse and evolving threats, hence, all these attacks are bound to develop in parallel with our growing dependence on digital devices, the internet, and new future technologies.

The botnets can be counted as attacks, as well as programs for future attacks, with this as the foundational prospect, this study explores how a botnet described and organized, how it is created, and used.

How to Prevent?

This is one of the frequent DNS attacks which have been faced by the victims every day, thus to mitigate these type of attacks, we have mentioned below few steps so that it will be helpful for you.

At first, understand your vulnerabilities properly.
Next, secure the IoT devices.
Identify both your mitigation myths from facts.
Discover, classify and control.

Conclusion

As you see, DNS service is essential for preserving your companies’ websites and online assistance working day-to-day. Thus if you’re looking for methods to evade these kinds of DNS attacks, then this post will be helpful for you. So, what do you think about this? Simply share all your views and thoughts in the comment section below. And if you liked this post then simply do not forget to share this post with your friends and family.

Microsoft Says Its Systems Were Also Breached in Massive SolarWinds Hack

The massive state-sponsored espionage campaign that compromised software maker SolarWinds also targeted Microsoft, as the unfolding investigation into the hacking spree reveals the incident may have been far more wider in scope, sophistication, and impact than previously thought.

News of Microsoft’s compromise was first reported by Reuters, which also said the company’s own products were then used to strike other victims by leveraging its cloud offerings, citing people familiar with the matter.

The Windows maker, however, denied the threat actor had infiltrated its production systems to stage further attacks against its customers.

In a statement to The Hacker News via email, the company said —

“Like other SolarWinds customers, we have been actively looking for indicators of this actor and can confirm that we detected malicious SolarWinds binaries in our environment, which we isolated and removed. We have not found evidence of access to production services or customer data. Our investigations, which are ongoing, have found absolutely no indications that our systems were used to attack others.”

Characterizing the hack as “a moment of reckoning,” Microsoft president Brad Smith said it has notified over 40 customers located in Belgium, Canada, Israel, Mexico, Spain, the UAE, the UK, and the US that were singled out by the attackers. 44% of the victims are in the information technology sector, including software firms, IT services, and equipment providers.

CISA Issues New Advisory

The development comes as the US Cybersecurity and Infrastructure Security Agency (CISA) published a fresh advisory, stating the “APT actor [behind the compromises] has demonstrated patience, operational security, and complex tradecraft in these intrusions.”

“This threat poses a grave risk to the Federal Government and state, local, tribal, and territorial governments as well as critical infrastructure entities and other private sector organizations,” it added.

But in a twist, the agency also said it identified additional initial infection vectors, other than the SolarWinds Orion platform, that have been leveraged by the adversary to mount the attacks, including a previously stolen key to circumvent Duo’s multi-factor authentication (MFA) to access the mailbox of a user via Outlook Web App (OWA) service.

Digital forensics firm Volexity, which tracks the actor under the moniker Dark Halo, said the MFA bypass was one of the three incidents between late 2019 and 2020 aimed at a US-based think tank.

The entire intrusion campaign came to light earlier this week when FireEye disclosed it had detected a breach that also pilfered its Red Team penetration testing tools.

Since then, a number of agencies have been found to be attacked, including the US departments of Treasury, Commerce, Homeland Security, and Energy, the National Nuclear Security Administration (NNSA), and several state department networks.

While many details continue to remain unclear, the revelation about new modes of attack raises more questions about the level of access the attackers were able to gain across government and corporate systems worldwide.

Microsoft, FireEye, and GoDaddy Create a Killswitch

Over the last few days, Microsoft, FireEye, and GoDaddy seized control over one of the main GoDaddy domains — avsvmcloud[.]com — that was used by the hackers to communicate with the compromised systems, reconfiguring it to create a killswitch that would prevent the SUNBURST malware from continuing to operate on victims’ networks.

For its part, SolarWinds has not yet disclosed how exactly the attacker managed to gain extensive access to its systems to be able to insert malware into the company’s legitimate software updates.

Recent evidence, however, points to a compromise of its build and software release system. An estimated 18,000 Orion customers are said to have downloaded the updates containing the back door.

Symantec, which earlier uncovered more than 2,000 systems belonging to 100 customers that received the trojanized SolarWinds Orion updates, has now confirmed the deployment of a separate second-stage payload called Teardrop that’s used to install the Cobalt Strike Beacon against select targets of interest.

The hacks are believed to be the work of APT29, a Russian threat group also known as Cozy Bear, which has been linked to a series of breaches of critical US infrastructure over the past year.

The latest slew of intrusions has also led CISA, the US Federal Bureau of Investigation (FBI), and the Office of the Director of National Intelligence (ODNI) to issue a joint statement, stating the agencies are gathering intelligence in order to attribute, pursue, and disrupt the responsible threat actors.

Calling for stronger steps to hold nation-states accountable for cyberattacks, Smith said the attacks represent “an act of recklessness that created a serious technological vulnerability for the United States and the world.”

“In effect, this is not just an attack on specific targets, but on the trust and reliability of the world’s critical infrastructure in order to advance one nation’s intelligence agency,” he added.

How to Use Password Length to Set Best Password Expiration Policy

One of the many features of an Active Directory Password Policy is the maximum password age. Traditional Active Directory environments have long using password aging as a means to bolster password security. Native password aging in the default Active Directory Password Policy is relatively limited in configuration settings.

Let’s take a look at a few best practices that have changed in regards to password aging. What controls can you enforce in regards to password aging using the default Active Directory Password Policy? Are there better tools that organizations can use regarding controlling the maximum password age for Active Directory user accounts?

What password aging best practices have changed?

Password aging for Active Directory user accounts has long been a controversial topic in security best practices.

While many organizations still apply more traditional password aging rules, noted security organizations have provided updated password aging guidance. Microsoft has said that they are dropping the password-expiration policies from the Security baseline for Windows 10 v1903 and Windows Server v1903. The National Institute of Standards and Technology (NIST) has long offered a cybersecurity framework and security best practice recommendations.

As updated in SP 800-63B Section 5.1.1.2 of the Digital Identity Guidelines – Authentication and Lifecycle Management, note the following guidance:

“Verifiers SHOULD NOT require memorized secrets to be changed arbitrarily (e.g., periodically). However, verifiers SHALL force a change if there is evidence of compromise of the authenticator.” NIST helps to explain the guidance change in their FAQ page covering the Digital Identity Guidelines.

It states: “Users tend to choose weaker memorized secrets when they know that they will have to change them in the near future. When those changes do occur, they often select a secret that is similar to their old memorized secret by applying a set of common transformations such as increasing a number in the password. This practice provides a false sense of security if any of the previous secrets has been compromised since attackers can apply these same common transformations. But if there is evidence that the memorized secret has been compromised, such as by a breach of the verifier’s hashed password database or observed fraudulent activity, subscribers should be required to change their memorized secrets. However, this event-based change should occur rarely, so that they are less motivated to choose a weak secret with the knowledge that it will only be used for a limited period of time.”

With the new guidance from the above organizations and many others, security experts acknowledge that password aging, at least in itself, is not necessarily a good strategy to prevent the compromise of passwords in the environment.

The recent changes in password aging guidance also apply to traditional Microsoft Active Directory Password Policies.

Active Directory Password Policy Password Aging

The capabilities of the password change policies in default Active Directory Password Policies are limited. You can configure the maximum password age, and that is all. By default, Active Directory includes the following Password Policy settings:

Enforce password history
Maximum password age
Minimum password age
Minimum password length
Minimum password length audit
Password must meet complexity requirements
Store passwords using reversible encryption

When you double click the maximum password age, you can configure the maximum number of days a user can use the same password.

When you look at the explanation given for the password age, you will see the following in the Group Policy setting:

“This security setting determines the period of time (in days) that a password can be used before the system requires the user to change it. You can set passwords to expire after a number of days between 1 and 999, or you can specify that passwords never expire by setting the number of days to 0. If the maximum password age is between 1 and 999 days, the minimum password age must be less than the maximum password age. If the maximum password age is set to 0, the minimum password age can be any value between 0 and 998 days.”

Defining the maximum password age with Active Directory Password Policy

With the default policy setting, you really can either turn the policy on or off and then set the number of days before the user password expires. What if you had further options to control the maximum password age and set different values based on the password complexity?

Specops Length Based Password Policy

As mentioned, recent guidance from many cybersecurity best practice authorities recommends against forced password changes and details the reasons for this change. However, many organizations may still leverage password aging as a part of their overall password security strategy to protect against user passwords falling into the wrong hands. What if IT admins had features in addition to what is provided by Active Directory?

Specops Password Policy provides many additional features when compared to the default Active Directory Password Policy settings, including password expiration. One of the options contained in the Specops Password Policy is called “Length based password aging.

Using this setting, organizations can define different “levels” of password expiration based on the user password’s length. It allows much more granularity in how organizations configure password aging in an Active Directory environment compared to using the default Active Directory Password Policy configuration settings.

It also allows targeting the weakest passwords in the environment and forcing these to age out the quickest. You will note in the screenshot. The length-based password aging in Specops Password Policy is highly configurable.

It includes the following settings:

Number of expiration levels – Enter how many expiration levels there will be. An expiration level determines how many extra days the user will have until their password expires and they are required to change it. This depends on how long the user’s password is. To increase the number of levels, move the slider to the right. The maximum number of expiration levels that can exist is 5.
Characters per level – The number of additional characters per level that define the extra days in password expiration
Extra days per level – How many additional expiration days each level is worth.
Disable expiration for the last level – Passwords that meet the requirements for the final expiration level in the list will not expire.

Configuring the Length based password policy in Specops Password Policy

Specops allows easily notifying end-users when their password is close to expiring. It will inform end-users at login or by way of sending an email notification. You can configure the days before expiration value for each of these settings.

Configuring password expiration notifications in Specops Password Policy

Organizations define the minimum and maximum password length configurations in the Password Rules area of the Specops Password Policy configuration. If you change the minimum and maximum password length configuration, the password length values in each level of the length-based password expiration will change as well.

Configuring the minimum and maximum password length

Combined with other Specops Password Policy features, such as breached password protection, the length-based password expiration strengthens enterprise password policies for both on-premises and remote workers.

Wrapping Up

Password aging has long been a feature of Active Directory Password Policies in most enterprise environments. However, as attackers get better at compromising passwords, new security best practice guidance is no longer recommending organizations make use of standard password aging.

Specops Password Policy provides compelling password aging capabilities that allow extending password aging features compared to default Active Directory Password Policies. By adding expiration levels, Specops Password Policy allows effectively targeting weak passwords in the environment by quickly aging these passwords out. End-users can use strong passwords much longer.

Organizations can even decide never to expire specific passwords that meet the defined password length. Using Specops Password Policy features, including length-based password expiration, helps to ensure more robust password security in the environment. Click here to learn more.