Unveiling the Crucial Role of Endpoints in Network Security

Unveiling the Crucial Role of Endpoints in Network Security

In the ever-evolving landscape of cybersecurity, the significance of endpoint security has surged to the forefront of discussions. This prominence has been further accentuated by the widespread transition of numerous businesses towards remote work arrangements. To embark on a comprehensive exploration of this topic, we must first establish a clear understanding of what endpoints entail. Endpoints, in essence, represent the end-user devices that encompass desktops, laptops, and mobile devices. They function as pivotal access points to an enterprise network, thereby creating gateways that nefarious actors may exploit. Given that end-user workstations constitute a substantial proportion of endpoints, our focus will be directed towards fortifying their security.

The Hierarchical Spectrum of Endpoint Security

The visual representation provided above underscores the fundamental role of endpoints as virtual gateways, acting as conduits to applications, services, and data within a user’s system. When compromised, these endpoints can serve as launching pads for infiltrating other workstations and even the privileged servers and users within an organization. 

Let us delve into a selection of scenarios wherein a compromise of endpoints may culminate in potential security incidents. 

Establishing Ingress to Endpoints

Primarily, one must discern how malicious entities manage to infiltrate endpoints. The advent of the pandemic compelled a seismic shift towards remote work practices, a transition that bore substantial implications for network security. To facilitate the transition to remote work, various security restrictions had to be temporarily relaxed. An illustrative example involves the exploitation of port 3389, conventionally employed for remote connections.

Some organizations deploy virtual private networks (VPNs) to establish secure network connections, especially for remote access. However, a growing number of malware variants, propagated by various hacking groups, are targeting vulnerabilities within VPN applications. The vital question that emerges is whether organizations effectively monitor incoming traffic through their VPNs, changes in VPN configurations, and the sources of VPN logins. If this aspect remains unmonitored, the time has arrived to commence oversight.

Another disconcerting trend revolves around Microsoft 365 macro attacks, executed through Microsoft 365 documents harboring malware. An assailant from their dedicated server can utilize built-in command line tools, such as PowerShell or Terminal in Linux, to craft a malware-laden Office macro. Subsequently, these attackers employ phishing tactics to induce users into opening the macro, thereby initiating cyberattacks. One potential outcome may involve capturing users’ password hashes, which are subsequently transmitted to a remote server.

Endowing Attackers with Persistence and Data Access

Armed with insights into the initial compromise of endpoints, it is crucial to consider how assailants may proceed to establish persistence within an endpoint, access data, infiltrate other endpoints, or compromise privileged servers and users.

Privilege Escalation via Enterprise-Critical Applications and Services Running on Endpoints

A substantial proportion of services operational on Windows endpoints utilize predefined local system accounts. When an attacker successfully infiltrates an endpoint through a local system account, they gain the requisite privileges to scrutinize critical services that operate under the aegis of local system rights. Manipulating these permissions allows access to business-critical data. 

In some instances, attackers may redirect the binary of the service towards a script or application of their choice, to be executed with local system privileges. Notably, a user account configured to manage a specific service may possess unintended privileges, potentially exploitable by an attacker. This pertains to Linux systems as well. 

Aside from exploiting misconfigured applications and services, attackers may introduce malevolent applications that execute malware post-installation. Frequently, attackers leverage MSI files, known as Windows installer files, to circumvent administrator-imposed restrictions within the network. For instance, even when the network administrator has prohibited the usage of Windows Command Prompt or PowerShell through AppLocker rules, attackers can employ malicious MSI files to bypass these constraints. The cloaking of an MSI file as a PNG file serves to maintain the assailant’s covert operations. MSI files may also be harnessed to introduce clandestine alterations to the network, such as adding new users to privileged groups in Active Directory, such as administrators. Mitigating these threats necessitates comprehensive monitoring of suspicious applications and processes across all endpoints.

Access to Business-Critical Data from an Endpoint 

Once an attacker attains local user access to an endpoint, they can peruse all locally stored data, encompassing files and folders. Yet, when equipped with a legitimate network user account, the assailant gains the ability to access data shared among network users via network shares. As elaborated upon earlier, there are numerous methodologies through which attackers can capture network user passwords.

Access to Other Endpoints from a Compromised Endpoint 

Beyond the aforementioned techniques, a recurring oversight entails the reliance on a single local administrator account for configuring endpoints within networks. This predicament arises from the reuse of the local admin password across endpoints, signifying that local admin access to one endpoint potentially extends to other endpoints within the network.

Monitoring and Detection 

The realization of an endpoint infection with malware underscores the imperative of monitoring every alteration within endpoints. Malware often lodges itself within legitimate OS-approved locations within the endpoint to evade detection. For instance, these locations may encompass registry keys or alternate data streams. The malware may also create new processes or terminate existing ones.

In summary, the comprehensive monitoring and tracking of security changes persistently across endpoints constitute the sole recourse for detecting unusual activities. This vigilance extends to commonplace activities, such as user logins to the network from their endpoints outside of work hours, which may harbor latent security threats.

In this context, security auditing assumes paramount significance in shielding endpoints from security breaches. Security events are meticulously documented in the form of audit logs within both Windows and Linux endpoints. Analyzing these logs is essential to uncover security irregularities. Forwarding Windows event logs and Linux syslogs from endpoints to a central server for aggregation, monitoring, and analysis is common practice. However, the core challenge resides in deciphering and understanding the security events, filtering and sorting techniques for specific events, correlating and amalgamating events to glean their underlying significance, and prioritizing and generating alerts for critical security events across endpoints.

These four fundamental parameters serve as a robust framework for unearthing sensitive or suspicious activities across endpoints, allowing for preemptive threat mitigation before they escalate into full-blown security incidents.

It is essential to adopt a proactive stance, keeping abreast of critical fixes and patches while diligently scrutinizing servers for potential vulnerability exploitation. In doing so, networks can proactively fortify their defenses against potential intrusions via endpoints.

In conclusion, security breaches often originate from the compromise of endpoints, making them a focal point in network security. A heightened state of vigilance, meticulous monitoring, and proactive security measures are indispensable in safeguarding endpoints from cyberattacks and the ensuing consequences. By adhering to these principles, organizations can fortify their network security and minimize the vulnerabilities associated with endpoints, bolstering their resilience in the face of evolving cyber threats. If you want to have more protection or want to learn more about network security, make sure you contact us, and we will help you with your questions. Learn more about SanaTechGs and ManageEngine, and for more tips, you can visit our blog.