Hybrid mesh firewalls need identity-aware microsegmentation for lateral movement

At a glance

What this is: This is a vendor analysis of hybrid mesh firewalls showing that centralized perimeter control does not stop lateral movement without identity-aware microsegmentation.

Why it matters: It matters because IAM, NHI, and security teams need enforcement that follows identities and workloads inside the environment, not just at the edge.

By the numbers:

• Gartner forecasts that more than 60% of organizations will have multiple firewall deployments by 2026.
• 9 of the Fortune 10 companies are included in that customer base.

👉 Read Zero Networks' analysis of hybrid mesh firewalls and microsegmentation

Context

Hybrid mesh firewalls are built to centralize policy across fragmented environments, but they are still network controls first and identity controls second. The problem is simple: once an attacker gets inside a segment, perimeter-centric tooling does not automatically follow the identity, workload, or service account involved in the move.

For IAM and NHI practitioners, that gap matters because lateral movement is often an identity problem disguised as a network problem. When east-west traffic is not governed by identity-aware policy, the environment can remain technically segmented while still being operationally permissive inside the blast radius.

Key questions

Q: How should security teams limit identity-driven lateral movement in hybrid environments?

A: Security teams should segment identity paths by privilege, business criticality, and trust boundary, then enforce different controls for privileged users, suppliers, and standard users. The goal is to stop a valid session in one domain from becoming a free pass into others. Identity-layer segmentation works best when combined with strong verification at every reset, escalation, and remote access step.

Q: Why do hybrid mesh firewalls not fully solve east-west risk?

A: Hybrid mesh firewalls simplify boundary policy, but they are still primarily network controls. They do not automatically follow identities, workloads, or service accounts inside a segment, so an attacker who gets inside can often move laterally unless internal access is separately constrained.

Q: What do security teams get wrong about microsegmentation?

A: Teams often treat microsegmentation as a networking feature rather than an identity enforcement layer. That mistake leads to coarse policies, stale rules, and false confidence that internal movement is contained when the real control boundary has not been defined tightly enough.

Q: Who is accountable when lateral movement controls are missing?

A: Accountability should sit with both security leadership and the teams that own identity, platform, and network policy, because lateral movement is a shared control problem. Frameworks such as NIST CSF and OWASP NHI make it clear that internal access, visibility, and containment are governance responsibilities, not optional hardening tasks. Ownership must be explicit before an incident forces the issue.

Technical breakdown

Why perimeter-centric firewalls miss east-west movement

Hybrid mesh firewalls consolidate policy across cloud, on-premises, and remote environments, but they are still optimized for north-south control. That means they are strong at managing ingress and egress at larger boundaries, yet they usually do not evaluate every internal hop against identity context. Without per-asset or per-identity enforcement, internal traffic can remain broadly reachable even when the perimeter is tightly managed. In practice, this creates a visibility gap between what the firewall can see and what the attacker can traverse after initial access.

Practical implication: teams should treat mesh firewall consolidation as boundary control, not as a replacement for internal identity-aware segmentation.

How identity-aware microsegmentation changes enforcement

Identity-aware microsegmentation moves enforcement closer to the workload, host, or identity, so policy follows the thing communicating rather than the network zone alone. That matters because east-west traffic is often where attackers pivot, enumerate, and expand access. Automated policy updates also reduce the drift that occurs when assets are added, moved, or decommissioned faster than firewall rules are maintained. The important change is not just finer granularity. It is that access decisions become tied to identity and context instead of static network membership.

Practical implication: align segmentation policy to workload and identity inventory, then automate updates as assets and services change.

Why automation matters in hybrid and cloud sprawl

In hybrid estates, manual rule maintenance becomes the weak point because every new subnet, workload, or service adds policy debt. Automated microsegmentation reduces that debt by continuously adjusting controls as infrastructure changes, which is especially relevant in environments that mix cloud, on-premises, and distributed locations. The security value is containment. When access is narrowly defined and updated dynamically, an attacker who compromises one system has far fewer reachable paths to traverse. That is the mechanism that limits blast radius once initial access has already occurred.

Practical implication: prioritize dynamic policy generation and continuous inventory sync over static segmentation designs that age out quickly.

Threat narrative

Attacker objective: The attacker’s objective is to expand from a single foothold into broader internal access by moving laterally across the hybrid environment.

1. Entry occurs when an attacker gains a foothold through the perimeter or another externally exposed access path, then lands inside a segment that is still broadly reachable.
2. Escalation follows as the attacker moves east-west across internal systems, using the absence of identity-aware controls to reach adjacent hosts, workloads, or services.
3. Impact arrives when the attacker expands the blast radius, accesses additional systems, and maintains movement paths that perimeter firewalls were never designed to contain.

Breaches seen in the wild

• MITRE ATT&CK Enterprise Matrix — MITRE ATT&CK Enterprise — adversary tactics and techniques, threat detection, attack chain mapping, credential access, lateral movement, privilege escalation.
• Cisco DevHub NHI breach — IntelBroker exploited exposed Cisco credentials, API tokens and keys in DevHub.

Read our 52 NHI Breaches Analysis report for a comprehensive view of breaches impacting Non-Human Identities including AI Agents.

NHI Mgmt Group analysis

Hybrid mesh firewalls solve policy sprawl, not identity sprawl. Centralizing perimeter management reduces operational friction, but it does not answer the harder question of which identity should be able to talk to which workload inside the environment. That distinction matters because lateral movement usually succeeds after the perimeter has already done its job. Practitioners should read mesh firewall consolidation as a control-plane simplification, not as a complete trust model.

Identity-aware microsegmentation is the missing internal control layer for hybrid estates. When communication paths are defined at the host, workload, or identity level, the attacker’s internal options shrink even if the perimeter is breached. This is why east-west protection belongs in the same governance conversation as IAM, PAM, and NHI oversight. The field should stop treating segmentation as a networking afterthought and start treating it as identity enforcement inside the blast radius.

Blast-radius control is the named concept that should replace perimeter confidence. The core problem is not whether a firewall exists, but whether it constrains the number of reachable systems after compromise. In hybrid environments, that concept becomes the real measure of control quality because static edge policy cannot keep pace with asset mobility. Practitioners should evaluate containment based on the smallest exploitable path, not the number of firewall consoles they have consolidated.

Automated policy updates matter because static segmentation decays as fast as infrastructure changes. The article’s own logic shows that distributed cloud, on-premises, and remote environments generate constant drift, which manual rules cannot track reliably. That creates a governance problem as much as a technical one, because stale access paths persist after decommissioning and workload changes. Security teams should treat continuous policy regeneration as part of access governance, not merely as a network hygiene task.

Hybrid mesh firewall strategy is becoming a layering problem, not a product-category problem. The market is moving toward stacked controls where central policy, identity awareness, and internal containment each solve a different part of the path to impact. That means practitioners must reassess whether their current architecture can enforce policy both at the boundary and within the segment. The decision is no longer firewall versus microsegmentation, but whether internal movement is actually governed at all.

From our research:

• 97% of NHIs carry excessive privileges, increasing unauthorised access and broadening the attack surface, according to Ultimate Guide to NHIs.
• From our research: Only 5.7% of organisations have full visibility into their service accounts, according to Ultimate Guide to NHIs.
• For a broader control lens: Review the attack-chain perspective in 52 NHI Breaches Analysis to see how privilege and movement paths translate into real incidents.

What this signals

Blast-radius control is becoming the practical test of hybrid network security. As estates span cloud, on-premises, and distributed sites, teams need to know whether a compromised identity can still move laterally after the boundary has been crossed. The more relevant question is no longer how many firewalls exist, but how much internal reach remains after compromise.

With 97% of NHIs carrying excessive privileges, the internal movement problem is not theoretical for identity teams. That figure, from the Ultimate Guide to NHIs, explains why segmentation, privilege scope, and workload reachability now need to be managed together rather than as separate programmes.

Identity-aware containment: this is the direction of travel for teams that want a defensible east-west strategy. The next step is to connect segmentation policy to NIST SP 800-207 Zero Trust Architecture so that trust decisions are continuously revalidated instead of assumed at the segment boundary.

For practitioners

• Map east-west exposure by identity and workload Build an inventory of which users, services, workloads, and device classes can reach each other inside major segments. Use that map to identify where the environment still relies on broad network reachability instead of identity-based restriction.
• Separate perimeter control from internal containment Keep hybrid mesh firewall policy as the boundary layer, then define a separate containment layer for workloads and internal systems. This prevents teams from assuming that external policy centralization automatically reduces lateral movement risk.
• Automate segmentation updates with infrastructure change Tie policy changes to asset onboarding, workload migration, and decommissioning events so internal access does not outlive the systems it was built for. Manual maintenance is too slow for hybrid environments with frequent change.
• Validate blast radius with controlled movement tests Test whether a compromised foothold can traverse adjacent systems before you declare the segmentation model effective. Focus on reachable paths, not policy counts, because attacker value comes from movement options, not from how many rules exist.

Key takeaways

• Hybrid mesh firewalls reduce policy sprawl, but they do not by themselves stop lateral movement inside a segment.
• Identity-aware microsegmentation is the control that narrows internal reach and limits the blast radius after initial access.
• For practitioners, the key question is not how many firewall tools exist, but whether internal paths are governed by identity and updated continuously.

Key terms

• Hybrid Mesh Firewall: A hybrid mesh firewall is a centrally managed approach that coordinates multiple firewall types across cloud, on-premises, remote, and distributed environments. Its value is policy consistency, but its control boundary still remains network-centric unless paired with identity-aware internal enforcement.
• Identity-Aware Microsegmentation: Identity-aware microsegmentation applies access controls at the level of workloads, hosts, services, or identities rather than only at the network zone. It is designed to reduce east-west reachability and contain compromise inside a smaller blast radius.
• Blast Radius: Blast radius is the amount of environment an attacker can reach after compromising a single foothold. In identity and segmentation work, it is the practical measure of whether controls actually limit internal expansion or merely document it.
• East-West Traffic: East-west traffic is communication between internal systems inside the environment, such as workload-to-workload or host-to-host connections. It is a primary route for lateral movement, so it must be governed with the same rigor as external access paths.

What's in the full article

Zero Networks' full article covers the operational detail this post intentionally leaves for the source:

• A breakdown of how the hybrid mesh firewall model is positioned across physical, virtual, cloud-native, and FWaaS deployments.
• The vendor’s explanation of how automated, identity-aware microsegmentation is layered to close east-west visibility gaps.
• Referenced commentary from Gartner and Palo Alto Networks on market demand, consolidation, and integration context.
• Examples of the product and partner messaging used to describe centralized management and internal traffic control.

👉 Zero Networks' full post covers the firewall model, lateral movement gap, and the microsegmentation layer in more detail.

Deepen your knowledge

NHI governance, agentic AI identity, and machine identity lifecycle are core topics in our NHI Foundation Level course, the industry's only accredited NHI security programme. If you are responsible for identity security strategy or NHI governance in your organisation, it is worth exploring.