Zero Trust Starts with Zero Unknowns: Securing BFSI with Threat Exposure Intelligence

Many organisations find that adopting Zero Trust in practice is far more complex than updating a security policy or deploying new tools. Without a foundational understanding of what assets exist, where they are located, and how they are interconnected, verification becomes an exercise in assumption rather than certainty.

Visibility is the starting point for Zero Trust. Every device, application, user identity, and data flow must be continuously discovered, catalogued, and assessed before access decisions can be made. In sprawling BFSI environments (where digital transformation initiatives have layered cloud platforms, SaaS applications, third-party APIs, and legacy infrastructure) the attack surface is often dynamic and poorly understood.

A lack of asset visibility undermines Zero Trust efforts at their core. Policies built on outdated inventories or incomplete knowledge create gaps that adversaries can exploit. Shadow IT systems, unmonitored APIs, misconfigured cloud storage, and overprivileged third-party integrations all represent blind spots where attackers can bypass controls undetected.

Third-party dependencies are a major contributor to the risks this sector faces. Institutions often rely on vendors for services such as payment processing, customer onboarding, data analytics, and even core banking operations. Yet many of these third parties have their own supply chains, creating layers of indirect exposure that are difficult to map, monitor, or control. A vulnerability in a vendor’s system can become an open door into the primary institution’s environment, often without the organisation's immediate knowledge.

Meanwhile, the rapid adoption of cloud services adds another dimension of complexity. Misconfigured storage buckets, unsecured APIs, and unmanaged identities across multi-cloud architectures create attack surfaces that traditional on-premises defences were never designed to address. Shadow IT initiatives (or systems and applications deployed without official oversight) further expand this blind spot, often connecting sensitive data to internet-facing services outside of governance frameworks.

APIs, in particular, have become a growing source of exposure. In open banking ecosystems, poorly secured APIs can leak sensitive financial data or serve as initial footholds for adversaries seeking deeper network access. Without continuous discovery and security validation, organisations may not even be aware of which APIs are live, who can access them, or how securely they are configured. sensitive data to internet-facing services outside of governance frameworks.

In short, BFSI environments are highly dynamic and adversaries are well aware of this. Attackers actively exploit weak points across cloud, supply chain, and API ecosystems because they know financial institutions often struggle to maintain real-time visibility into these sprawling digital assets.

The first stage of Zero Trust is mapping the organisation’s real-world threat exposure. Without a comprehensive, continuously updated view of vulnerabilities, access pathways, and exploitable assets, Zero Trust policies risk being disconnected from the true attack surface.

Threat exposure mapping goes beyond traditional asset inventories. It builds a living model of how attackers could realistically move through the environment from an unmonitored API or misconfigured cloud resource to critical financial systems. This contextual understanding is essential to prioritise defences based not just on static vulnerability scores, but on actual business impact and exploitability.

For BFSI organisations managing hybrid environments (where customer data spans on-premises cores, SaaS platforms, and third-party networks) exposure mapping is especially vital. Shadow APIs, overprivileged vendor connections, and legacy systems often create invisible pathways that bypass traditional security controls. Without visibility into these dynamic exposure paths, Zero Trust segmentation, access policies, and authentication models risk being incomplete or misaligned with real-world risks.

Instead of relying on assumptions about what attackers might target, exposure mapping empowers security teams to focus resources where they matter most: on the pathways that genuinely pose existential risk to operations, regulatory compliance, and customer trust.

In the BFSI sector, unseen vulnerabilities carry consequences that extend far beyond technical disruption. The direct costs of a breach are staggering.

According to IBM’s 2025 Data Breach Report , the average financial sector breach now exceeds $5.56 million in damages, encompassing incident response, legal fees, customer notification, and regulatory fines. However, the indirect costs are often even greater and harder to recover from. Loss of customer trust can lead to lasting attrition, especially in an era where loyalty is increasingly tied to perceptions of digital security and privacy.

Reputational damage is particularly acute for financial institutions because they serve as custodians of the broader economic infrastructure. An incident involving exposed customer data, payment system downtime, or third-party compromise can ripple outward, impacting public markets, investor confidence, and even national economic stability. Regulatory scrutiny is intensifying as a result, with frameworks like GDPR, PCI DSS, POPIA, and FSCA demanding proactive third-party oversight, continuous monitoring, and rapid incident reporting.

Recent supply chain breaches have revealed just how fragile interconnected BFSI ecosystems have become. Institutions that lack continuous visibility into third-party risks or cloud exposures may find themselves held liable not just for their own lapses, but for vulnerabilities introduced deep within their vendor networks.

In July 2025, Allianz Life Insurance experienced a significant breach when attackers exploited a cloud-based CRM platform managed by a third-party vendor. The incident exposed sensitive data of 1.4 million customers, employees, and financial professionals.

This breach illustrates key failures across several CTEM phases. Weaknesses in scoping and discovery left the CRM system outside active monitoring. A lack of prioritisation and validation meant the system's business impact and attack pathways weren’t properly assessed or tested. As a result, attackers exploited a trusted integration point that wasn't treated with adequate scrutiny.

From a Zero Trust perspective, the CRM platform should have been segmented, continuously monitored, and treated as untrusted by default. Its compromise reinforces the need to apply Zero Trust and CTEM principles consistently. This is especially important in BFSI environments where third-party services are deeply embedded in critical operations.

While Zero Trust and Continuous Threat Exposure Management (CTEM) represent long-term strategic journeys, there are immediate actions BFSI institutions can take to strengthen their security posture today. By embedding CTEM principles early, organisations can achieve measurable improvements in visibility, risk reduction, and regulatory alignment.

1. Scoping: Discovery across cloud, on-premises, and third-party environments forms the foundation for effective exposure management. Institutions should focus on mapping APIs, SaaS applications, vendor integrations, and unmanaged assets that traditional visibility tools often overlook.

2. Discovery: Understanding how an organisation appears to adversaries is critical. Continuous external monitoring identifies exposed domains, leaked credentials, shadow IT assets, and misconfigurations before they can be exploited, thereby closing the gap between internal assumptions and external realities.

3. Prioritisation: Traditional CVSS-based vulnerability management often misaligns with real-world risk. By prioritizing vulnerabilities based on exploitability, exposure paths, and potential business impact, institutions can ensure security resources defend critical systems rather than being spread too thin across low-risk issues.

4. Validation: Controlled testing through red teaming, AI-driven attack path simulation, and purple teaming exercises enables organisations to validate the resilience of their controls safely. This transforms security posture from theoretical readiness to demonstrated operational resilience without risking disruption.

5. Mobilisation: Operationalizing CTEM insights through governance frameworks ensures leadership visibility and faster remediation. Embedding continuous exposure metrics into board reporting strengthens regulatory defensibility and positions cybersecurity as a proactive enabler of institutional trust and resilience.

By following the CTEM methodology BFSI security teams can move quickly from fragmented risk management toward proactive, intelligence-driven Zero Trust. These quick wins not only demonstrate immediate value to stakeholders but also lay the groundwork for sustainable, strategic cyber resilience.