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An advanced persistent threat (APT) is a wide-ranging term used to describe an attack drive in which a trespasser, or a group of trespassers, launches an illegitimate, long-term presence on a network in order to mine highly sensitive data. The targets of these attacks, which are very prudently selected and researched, classically include large enterprises or governmental networks.
The consequences of such invasions are massive, and include:
- Intellectual property theft (e.g., trade secrets or patents)
- Compromised sensitive information (e.g., employee and user private data)
- The disrupting of serious organizational infrastructures (e.g., database deletion)
- Total site takeovers
Implementing an APT attack requires more resources than a normal web application assault. The culprits are typically teams of skilled cybercriminals having considerable financial support. Some APT assaults are government-funded and used as cyber warfare weapons. APT attacks are different from conventional web application threats, because they’re significantly more complex. Also, they are not hit-and-run in nature, meaning that once a network is infiltrated, the culprit remains in order to achieve as much information as possible. What’s more, they’re manually performed against a particular mark and extensively launched against a large pool of targets. And contrary to one particular part, they often seek to infiltrate a whole network.
To establish a position in a targeted network, culprits regularly use more common assaults, such as remote file inclusion (RFI), SQL injection and cross-site scripting (XSS). Then, Trojans and backdoor shells are frequently used to enlarge that position and make a persistent presence within the targeted perimeter.
Advanced persistent threat (APT) progression
A successful APT attack can be divided into three categories: 1) network infiltration, 2) the expansion of the invader’s presence and 3) the extraction of collective data—all without being spotted.
Stage 1 – Infiltration
Companies are characteristically intruded through the compromising of one of three attack surfaces: web assets, network resources or approved human users. This is attained either through malevolent uploads (e.g., RFI, SQL injection) or social engineering assaults (e.g., spear phishing)—threats confronted by large organizations frequently.
Moreover, moles may concurrently perform a DDoS attack against their target. This serves both as a smoke screen to divert network workers and as a means of flagging a security perimeter, making it easier to breach. Once initial access has been attained, assailants rapidly install a backdoor shell. Backdoors can also come in the form of Trojans disguised as genuine pieces of software.
Stage 2 – Expansion
Once the foothold is recognized, assailants move to widen their presence within the network. This includes moving up an organization’s hierarchy, compromising staff members with access to the most complex data. In doing so, they’re able to collect serious business information, including product line info, employee data and financial records.
Depending on the eventual attack objective, the accrued data can be sold to a rival enterprise, changed to damage a company’s product line or used to take down an entire organization. If damage is the purpose, this phase is used to delicately gain control of multiple serious functions and operate them in a definite sequence to cause extreme harm. For example, invaders could erase whole databases within a company and then upset network communications in order to extend the retrieval process.
Stage 3 – Extraction
While an APT event is in progress, pilfered information is classically stored in a safe location inside the network being attacked. Once enough data has been gathered, the thieves need to extract it without being noticed. Generally, white noise strategies are used to divert your security team so the information can be moved out, which might take the form of a DDoS assault, again tying up network workers and/or flagging site defenses to ease extraction.
APT security measures
Network administrators, security providers, and individual users need to take a multi-dimensional approach for proper APT detection and protection. Monitoring ingress and egress traffic is thought to be the best practice for averting the installation of backdoors and blocking pilfered data withdrawal. Examining traffic inside your network perimeter can also help alert security workers to any unfamiliar conduct that may point to malevolent activity.
A web application firewall (WAF) positioned on the edge of your network sieves traffic to your web application servers, thus defending one of your most susceptible attack surfaces. As well as other functions, a WAF can help root out application layer assaults, such as RFI and SQL injection attacks, normally used during the APT penetration phase.
Internal traffic monitoring services can provide a grainy view displaying how users are interacting within your network, while helping to recognize internal traffic irregularities, (e.g., irregular logins or unusually large data transfers). The latter could indicate an APT attack is taking place. You can also screen access to file shares or system honeypots. Last but not least, incoming traffic monitoring services could be beneficial for sensing and eliminating backdoor shells. These can be recognized by interrupting remote requests from the operators.
Application and domain whitelisting
Whitelisting is a way of monitoring domains that can be reached from your network, as well as applications that can be fixed by your users. This is another useful technique of decreasing the success rate of APT assaults by curtailing existing attack surfaces. However, this security measure is far from failsafe, as even the most reliable domains can be compromised. It’s also a fact that malicious files usually arrive under the guise of genuine software. Furthermore, older software product versions are likely to be compromised and exploited. For effective whitelisting, stern update policies should be imposed to ensure your users are always running the latest version of any application appearing on the list.
Access control
For perpetrators, your workers characteristically embody the largest and most susceptible soft-spot in your security perimeter. Usually, this is why your network operators are regarded by prowlers as an easy doorway to penetrate your defenses, while increasing their hold within your security perimeter.
Here, expected targets fall into one of the following three categories:
- Thoughtless users who disregard network security policies and unwittingly grant access to possible threats.
- Hateful insiders who deliberately misuse their user identifications to grant culprit access.
- Compromised users whose network access privileges are compromised and used by attackers.
Developing effective controls needs a wide-ranging appraisal of everyone in your organization—especially the info to which they have access. For example, pigeon-holing data on a need-to-know basis helps block a prowler’s capacity to steal login credentials from a low-level staff member, using it to access delicate materials. Important network access points should be attained with two-factor authentication (2FA). It requires users to use a second form of verification when retrieving sensitive areas, preventing unlawful actors camouflaged as genuine users from moving around your network.
Additional measures
In addition to the aforementioned steps, patching network software and OS susceptibilities as quickly as possible is another great measure. Sifting incoming emails to avert spam and phishing attacks targeting your network should also be considered. Instant logging of security measures to help improve whitelists and other security policies is another amazing step.
Who is Vulnerable?
Before probing the safety measures that should be taken to avert APTs, users and decision-makers should realize what this style of attack entails. The procedure connected with APTs varies from other hacking methods, particularly on account of the number of steps this kind of penetration requires.
There are, typically, six stages involved with Advanced Persistent Threat solutions, the first of which being intelligence gathering. During this step, cybercriminals influence public information from renowned resources like social media sites to recognize precise targets and get some detail on the individual or company. They will then apply this information to launch a modified attack, aiming at the exact weaknesses of the victim.
Next, assailants create a point of entry from which they can launch the advanced persistent threat and steal sensitive data. Usually, a zero-day malware sample is used to firstly compromise the system. Once cybercriminals have entered the system, they exploit command and control communication to direct the malware infection, allowing the hackers to further misuse infected machines and move throughout the network. Through C&C communication, attackers can move sideways to launch and uphold persistent control of the network.
Then, the cyberthieves influence a range of different methods, including port scanning, to underscore the servers with the most sensitive data, thus establishing their theft plan. From here, the hackers can collect this information and send it to an internal staging server where the stolen content is crushed and encoded. It can then be conveyed to other, safer locations under the cybercriminals’ control, leading to the creation of cyber threat dashboard.
How APTs Can Be Prevented
While APT attacks can appear impossible to avert owing to their thorough, multi-faceted nature, it is generally observed that when each infiltration technique is scrutinized by itself, organizations can better prepare to guard against each one. This calls for advanced persistent threat solutions that make the job easier.
Many experts recommend the use of security best practices to guard against APTs, including ensuring that all security covers are installed and systems are up and running. Companies should frequently test their current defense measures to ensure they function as they should. Moreover, organizations should have a susceptibility management system in place to ensure a swift response and instant extenuation of any system attacks. Nevertheless, one of the best ways to guarantee a defense against APTs is to comprehend what content is top priority for protection. During the infection process, attackers take significant time to cherry-pick the information that will be the most worthwhile for the infiltration. Therefore, business leaders should also take time to recognize the most sensitive and lucrative data and put defenses in place, such as cyber threat dashboard, to guard these materials specifically.
