Top Cyber Risks in 2026: How to Avoid Hidden Network Vulnerabilities

Vulnerability exploitation now serves as the initial access vector for 20% of all breaches, rising 34% year-over-year. Meanwhile, credential abuse remains the #1 entry point for attackers, and third-party involvement in breaches doubled in the last year. The message for defenders? Hackers are getting better at weaponizing trusted systems and identities – it’s time to proactively address hidden threats and build resilience into your network.  

Find out where security weaknesses may be lurking in your environment with a look back at some of the year’s most damaging exploits and learn how you can prevent unseen cyber threats from becoming disruptive breaches in 2026. 

The Cyber Threat Landscape: How Attackers Target Tech Stacks 

The tools organizations use to keep everyday operations humming often hide some of the most dangerous vulnerabilities in modern networks. Tech designed to keep businesses connected, productive, and resilient ranked among attackers’ favorite entry points and lateral movement vectors in 2025.  

Avoiding hidden vulnerabilities in 2026 starts with understanding where your network security weaknesses may lie. Take a closer look at the systems attackers most often exploit and learn how you can stop trusted tools from turning into threats.  

VPNs and Remote Access Solutions: Initial Access and Lateral Movement Risks 

VPNs remain one of the most widely adopted solutions to keep employees and third-party vendors connected, but they’re insecure by default. Most solutions expose at least one TCP port to the internet, meaning anyone can try to hack a VPN with known vulnerabilities that aren’t yet patched – or unknown vulnerabilities that can’t be patched.  

What’s more, VPNs flatten trust with an “all or nothing” approach. Once connected through a VPN, users typically gain absolute access since traditional solutions lack device and user awareness, so it’s no surprise that most security leaders report lateral movement following VPN-related attacks – which are rising.  

Over 90% of security leaders express concern about VPNs leading to a security breach, and 56% of organizations experienced at least one VPN-related cyberattack in the last year.

VPN Exploits in 2025 

According to Verizon’s 2025 Data Breach Investigations Report, zero-day exploits targeting edge devices and VPNs grew almost eightfold year-over-year – a trend backed by a slew of real-world incidents. 

For example, Ivanti Connect Secure and Policy Secure vulnerabilities dominated early-year incident reporting. Attackers exploited command injection flaws and authentication bypasses in CVE-2024-21887 and CVE-2024-21893, then used newly discovered 2025 persistence mechanisms (like TRAILBLAZE/BRUSHFIRE) to outlive patch cycles. Meanwhile, Fortinet SSL-VPN bugs (including CVE-2024-21762) continued to provide entry points into critical infrastructure networks. 

Built-in Business Resilience Tips: How to Prevent Hidden VPN Risks in 2026 

• Build a Zero Trust architecture with comprehensive microsegmentation, cutting off excessive VPN access   
• Implement robust identity-based controls inside the network to prevent lateral movement  
• Modernize secure remote access with VPN alternatives like ZTNA to remove inherent weaknesses  

Firewalls and Security Appliances: Zero-Days Bypass Defenses 

Firewalls are designed to protect north-south traffic, stopping intrusions at the perimeter. But as sophisticated hackers grow faster, stealthier, and more well-resourced, they’re increasingly focused on exploiting these high-impact targets.  

Over 60% of enterprise-focused zero-day exploits target security and network products – a proportion that’s risen steadily in recent years. Google Threat Intelligence sums up the forces driving this increase simply:  

Attackers are intentionally targeting products that can provide expansive access and fewer opportunities for detection. 

In other words, compromising the solutions that organizations rely on for network visibility and perimeter defense gives attackers an easier path to breach the network and move laterally undetected. 

Firewall Exploits in 2025 

Palo Alto Networks’ PAN-OS vulnerability (CVE-2024-3400) remained a commonly weaponized exploit well into 2025. Attackers used the flaw to execute commands directly on GlobalProtect firewalls, harvest configuration data, and deploy persistent backdoors. 

Similarly, SonicWall Gen 7 firewalls were abused in several ransomware attacks across healthcare and regional service providers. Investigations uncovered hands-on-keyboard activity that allowed attackers to pivot from a single appliance into Active Directory, application servers, and internal management networks. 

Built-in Business Resilience Tips: How to Prevent Hidden Firewall Risks in 2026 

• Implement a layered network security strategy that combines next-gen firewalls, microsegmentation, and identity-based controls to protect every dimension of traffic – north-south, east-west, and up-down  
• Prioritize dynamic policy creation and enforcement to automatically adapt your security posture as network behavior changes  
• Adopt a Zero Trust mindset – assume that breaches are inevitable and lean into business resilience strategies

Cloud and Web Applications: Remote Code Execution Threats  

Cloud and web applications underpin core business operations – from customer portals and collaboration systems to internal dashboards and beyond, these tools keep organizations running, but a wave of framework-level vulnerabilities in 2025 proved how quickly a single flaw can throw an entire application stack off balance.  

Remote code execution (RCE) vulnerabilities – which not only grant initial access but also expose sensitive API keys, service tokens, or database connections embedded in application code or configuration files – have grown particularly prominent. Once attackers breach an internet-facing app, they can often traverse internal APIs and back-end services due to overly permissive accounts.  

Cloud and Web Exploits in 2025 

The React Server Components vulnerability (CVE-2025-55182), also known as “React2Shell,” rapidly became one of the most exploited flaws of the year. Within hours of public disclosure, threat actors (including espionage-linked groups) targeted React and Next.js applications, stealing credentials and deploying stealthy backdoors. 

Meanwhile, a critical SharePoint RCE (CVE-2025-53770) was exploited in the wild weeks before a patch was released. This vulnerability played a key role in the high-impact Colt Technology Services breach, leading to widespread telecom operations disruptions and major internal data exposure. 

Built-in Business Resilience Tips: How to Prevent Hidden Cloud App Risks in 2026 

• Limit lateral movement pathways with granular network segmentation to ensure hackers are immediately contained after a web compromise. 
• Secure machine identities like service accounts by restricting logon rights and asset access to operational needs only  
• Isolate critical systems to keep essential services running – even during an active attack 

Remote Monitoring and Management Tools: Supply Chain Exposure 

Remote Monitoring and Management (RMM) platforms streamline administration and software maintenance for IT teams and MSPs, but they also provide attackers with a mechanism for large-scale compromise. RMM tools have legitimate permissions to execute commands, deploy updates, remotely access and monitor devices, and more. In the wrong hands, this level of operational power can be weaponized, spreading breaches from trusted third parties in supply chain attacks.  

RMM compromise fueled damaging ransomware events in 2025, allowing threat actors to bypass traditional security controls and deploy malicious payloads under the guise of normal administrative activity. 

RMM Exploits in 2025 

Cybercriminal groups like Akira ransomware leveraged compromised RMM environments throughout 2025 to push malware to downstream customers. Many intrusions were linked to older ConnectWise ScreenConnect vulnerabilities that remained unpatched or stolen MSP credentials that enabled attackers to impersonate legitimate administrators. 

Built-in Business Resilience Tips: How to Prevent Hidden RMM Vulnerabilities in 2026 

• Implement network-layer MFA to enforce just-in-time verification for privileged access 
• Limit and protect third-party connections with a modern remote access solution  
• Enforce microsegmentation and identity segmentation to block lateral movement – even when attackers use legitimate credentials  

Hypervisors and Virtualization Management Planes: Privileged Pathways 

Virtualization platforms centrally host business apps, databases, development workloads, and even security tools. But this centralization creates an outsized risk: a single hypervisor compromise provides attackers access to every virtual machine running above it. 

This risk was on full display over the past year, as multiple ransomware operations reintroduced ESXi-targeted campaigns leveraging unpatched vulnerabilities and privilege escalation flaws. 

Virtualization Exploits in 2025 

Ransomware groups exploited ESXi vulnerabilities such as CVE-2024-37085 to escalate privileges on hosts and encrypt entire VM clusters. Several education, manufacturing, and government organizations faced multi-day outages as attackers moved from the hypervisor into backup systems, storage arrays, and AD-integrated infrastructure. 

Virtualization platforms like VMware vSphere have been so widely targeted in recent months that CISA issued an alert on BRICKSTORM malware, a sophisticated backdoor that allows adversaries to steal cloned virtual machine snapshots for credential extraction and create hidden, rogue VMs. 

Built-in Business Resilience Tips: How to Prevent Hidden Virtualization Risks in 2026 

• Apply robust access controls and MFA to virtualization admin access  
• Maintain real-time visibility into network behavior to more easily identify anomalous activity  
• Isolate hypervisors and all other assets into secure microsegments to stop hackers from pivoting across the network

Identity and Access Infrastructure: Tokens, OAuth, and Beyond 

Identity-based attacks are on the rise, with credential abuse ranking as the #1 initial access vector. Identity-related exploits are particularly tough to detect because they often blend in with legitimate network activity, relying on subtle misconfigurations, excessive permissions, or human error.  

Most networks weren’t built to secure identities as a distinct boundary, and this blind spot has become a common entry point for hackers  

Identity Exploits in 2025 

Some of the most actively exploited weaknesses in the identity sphere throughout 2025 related to cloud authorization tokens and trusted API integrations. In a striking example of this risk, attackers leveraged compromised OAuth access and refresh tokens associated with Salesloft Drift to gain unauthorized access to hundreds of Salesforce customer environments. Because the tokens were valid and trusted by Salesforce, attackers were able to access and exfiltrate CRM data and even embedded cloud credentials without triggering multi-factor authentication or typical login alerts.  

Built-in Business Resilience Tips: How to Prevent Hidden Identity Risks in 2026 

• Audit permissions regularly and revoke unused or unnecessarily broad access, adapting policies based on real network behavior  
• Secure logins with just-in-time MFA, applied based on real-time contextual factors  
• Granularly segment all network assets and identities to neutralize the threat of stolen credentials and prevent lateral movement  

Network Security Best Practices for 2026 

Attackers exploit a similar set of weaknesses across VPNs, firewalls, cloud apps, RMM platforms, hypervisors, and identity systems: flat networks, implicit trust, and over-privileged access. To harden your network and enhance business resilience, focus less on chasing CVEs or individual alerts and more on proactively minimizing your attack surface.  

Granularly Segment Network Assets and Identities  

Implementing microsegmentation and identity segmentation allows security teams to instantly contain threats, whether breaches start with a zero-day vulnerability, a compromised credential, or any number of hackers’ favorite tactics. Enforcing segmentation across both assets and identities unlocks true least privilege at scale.  

Disable Unnecessary Ports and Services  

Every open port is a potential backdoor – one of the best ways to proactively minimize attack surfaces is to close unused ports and disable unneeded services. For example, closing remote access protocols by default and opening them only when necessary (after MFA verification) cuts off an easy pathway for attackers.  

Operationalize Zero Trust Security  

Security teams should align architecture, processes, and incident response strategies with Zero Trust principles, verifying every connection explicitly, limiting access, and assuming breach across every layer of the stack. Controls should adapt alongside network changes, updating dynamically rather than relying on manual tuning.  

Enforce Just-in-Time MFA for Privileged Access  

Access to sensitive systems, privileged activities, or admin accounts needs more robust security measures to protect against rising identity threats. With network-layer MFA, organizations secure everything from databases and OT systems to legacy applications and beyond, further minimizing the risk of credential misuse.  

Maintain Comprehensive Network Visibility  

You can’t secure what you can’t see. Organizations need a complete picture of their networks – every asset, identity, and connection – to understand where security gaps may lie and to keep a pulse on activity.  

Build a Resilient, Self-Defending Architecture with Zero Networks  

With Zero Networks, it’s easier than ever to proactively block threats and keep operations running smoothly. Our automated, identity-aligned microsegmentation solution delivers a containment layer to isolate and neutralize cyberattacks in real time.  

Dynamic policy creation, deep visibility into network activities, and comprehensive coverage across assets and identities enable Zero to support a self-defending network architecture that remains resilient against sophisticated attackers and hidden vulnerabilities.  

See for yourself how Zero Networks can measurably improve your security posture without the manual effort – request a demo.