What Is an Advanced Persistent Threat (APT)?

The Main Objectives of APTs

Due to how sophisticated most APTs can be, they are typically only used on high-value targets or when the malicious group perpetrating the attack knows they will gain from a successful breach. Normally, the main objective of an APT is a reflection of the business that is being targeted. For example, a government agency might be targeted for espionage, while a finance company might be targeted due to holding valuable customer data.

Here are some potential objectives for an advanced persistent threat:

• Exfiltrate Data: Once an APT gains sufficient control over a company’s data architecture, often through lateral movement, it may reach a point where it has visibility into critical company systems. At this stage, the APT may focus entirely on mass exfiltration, sending as much sensitive data as possible to the attacking group.
• Hijack Important Information: APTs often sit in a company’s data architecture without doing anything, potentially for many months. When they receive highly confidential or sensitive information that is valuable to the attacking group, they may kick into action to exfiltrate this vital data.

Long-Term Surveillance: APTs may simply observe company data for a significant period of time, gathering information about the strategy or main objectives of the business. It could even map out what technologies or internal processes the company uses, delivering this information to competitors to help narrow a competitive advantage.

The Three Stages of an APT Attack

An advanced persistent threat is one of the most intelligent forms of cyber security attacks, as it prioritizes remaining hidden rather than creating damage or exfiltrating large amounts of data. A team running an APT would prefer small exfiltrations over many months or years rather than a bulk one-time attack.

Here are the main stages of an APT attack:

1. Infiltration: The first stage of an APT attack is infiltration, where cyber criminals manage to break through or bypass company security defenses. APTs often attempt to fly under the radar, so the specific attack vectors used at this stage will likely be less destructive than other breaches. Most commonly, this phase will use phishing events or social manipulation as the primary vector.
2. Lateral Movement: Once a malicious threat has access to your company’s network, it will attempt to move laterally to infect other systems. Again, as APTs aim to exist without drawing any attention to their presence, this will likely be a slow but consistent process. The threat may directly move to other exposed systems, or the team behind the threat may try to gather more user credentials to log in to other parts of your network system. At this stage, attackers may also use their presence in a company’s network to create a backdoor for further exploitation, like downloading their own software into the company ecosystem.
3. Data Exfiltration: Once an APT has sufficiently embedded itself in a company’s network, it will begin to exfiltrate sensitive data from the company back to the attacking group. Most of the time, this is done concurrently with another attack, using a secondary vector to act as a diversion to occupy the security team. While a team aims to stop the more prominent threat, the APT will exfiltrate as much data as possible in secret. An APT always prioritizes remaining hidden.

As APTs aim to exist in a system for as long as possible, their lifecycle doesn’t necessarily end with data exfiltration. They may stop exfiltration and reduce the activity of the threat for a short period of time, making it seem like a cyberdefense team was able to neutralize their threat. All the while, they can continue to hijack information and steal data on a smaller scale.

Common Attack Techniques

Due to their complexity and sophistication, it’s rare to find two APTs that use the same vectors. Most of the time, malicious groups will plan out an APT that is custom-built for the company they are going to attack. With that in mind, many of the most common attack techniques revolve around spear-phishing et Ingénierie sociale strategies.

Here is a quick overview of how APT attacks may begin:

• Spear-Phishing: A deeply personal, well-planned phishing campaign launched at an IT admin or executive in a company.
• Zero-Day Exploits: Attackers may make use of a zero-day exploit to download malware to a company’s ecosystem without their knowledge.
• Supply Chain Compromise: If any vendor (upstream or downstream) that connects to a company is involved in a breach, an APT may laterally transfer to the company and begin its infiltration.
• Misconfigured Apps: SaaS solutions or cloud apps that have misconfigured security policies may provide an entry point for APT attacks.
• Remote Access Trojans (RATs): A RAT file that successfully enters a business network may provide attacking groups the access they need to then create a hidden APT deep in a company system. 

How to Detect an APT Attack: The Telltale Signs

While APTs will often exhibit as few signs as possible, they are not completely invisible. If your cybersecurity team knows what to look for, you can identify a few telltale signs that signal an unauthorized presence in your systems.

These are the main signs that an APT is currently active in your business: 

• Strange Account History: If you notice an account with data privileges viewing files or accessing systems at strange hours, especially outside of the working hours of the person who owns that account, someone else might have access.
• Unfamiliar Data Access Patterns: A sudden request to access a large volume of files or strange database queries might signal that the person requesting access isn’t who they say they are.
• Spikes in Traffic: Any spike in traffic, especially when moving externally to an unfamiliar location, could signal that an exfiltration event is occurring. 
• System Changes: When security admins review current permissions configurations and notice subtle unauthorized changes, they may have an active APT attack on their hands.

While drastic signals will instantly alert security engineers, the precision of APTs is that many of these signals will happen on a heavily reduced scale. Due to this, businesses need to prepare holistically, fortify existing security defenses, and actively monitor their environments for subtle shifts that could indicate an APT attack.

Real-World Examples

Potentially the most successful APTs in history are those that were never (or still have not been) fully disclosed. Existing threats that still manage to remain undetected could be actively working within major organizations and government networks.

Active threats aside, there have been a number of major real-world APTs over the past few years:

• 2020 SolarWinds Attack: SolarWinds was a trusted third-party provider that worked with government agencies and some of the largest companies in the world. Establishing an APT in SolarWinds software, hacking groups were able to gain access via the software supply chain into major organizations and exfiltrate information.
• 2023 MOVEit Attack: After exploiting a vulnerability in MOVEit Transfer, a group of malicious actors was able to exfiltrate data from a large volume of connected companies, including US federal agencies and major financial services businesses.

Often, the APTs that come to light are those that arrive through the software supply chain and exploit a vulnerability in a third-party service. In a more unique case where an APT targets one specific company, they are much harder to identify and eradicate. 

Best Practices to Mitigate APTs

An APT is a dynamic and challenging threat to detect, let alone neutralize. Due to the diverse range of underlying threat vectors that an APT could use, a company’s best option to protect itself is to use a holistic approach.

Here are several best practices that, in tandem, work to mitigate APTs:

• Déployer Pare-feux pour applications Web
• Patch Software Systems Regularly
• Enforce Strict Contrôles d'accès
• Whitelist Approved Applications and Company Domains 
• Utiliser Threat Intelligence Networks
• Conduct Regular Internal Threat Hunting and Detection
• Perform Penetration Tests Regularly
• Monitor Incoming and Outgoing Network Traffic 

Secure Your Network with CloudGuard

Considering how valuable private customer information is to cybercriminals, an advanced persistent threat that lingers inside your organization and continues to exfiltrate or listen in on sensitive data is extremely dangerous. Traditional security solutions that prioritize signature-based detection may struggle to identify APTs, as they are notoriously difficult to track and alter their structure to remain undetected.

Check Point CloudGuard is the most effective solution for identifying and neutralizing APTs, using AI-first systems to preemptively flag and prevent threats. Even in zero-day events, where no defined signatures exist, CloudGuard is able to accurately detect threats and minimize them, fine-tuning its defensive systems in real time.

Avec CloudGuard WAF, businesses can protect their business with a 99.4% threat detection rate, having blocked 100% of zero-day attacks. Put your company’s security first and Demander une démonstration today to get started.