By Yinka Ajayi

Abdullateef Tunde Abdulsalam, a cybersecurity analyst at a major UK financial institution and founder of Fa3Tech Limited, has raised concerns over a critical but often overlooked vulnerability within the banking sector, warning that expired digital certificates could trigger widespread service disruptions if left unmanaged. Abdulsalam, whose work focuses on strengthening digital security infrastructure and developing practical, scalable solutions to emerging cyber risks, shared this insight in an operational resilience analysis published in March 2026. He noted that the next major disruption in UK financial services may arise not from a coordinated cyberattack but from unnoticed failures within routine digital processes that underpin everyday banking operations.

He pointed to real-world scenarios where financial platforms have abruptly gone offline, leaving customers unable to access accounts or complete transactions. In many such cases, organisations initially suspect malicious activity, prompting urgent incident response protocols, only to discover that the root cause was an expired certificate. “To a customer, the experience is indistinguishable from a cyberattack,” Abdulsalam explained, highlighting how quickly trust can erode when digital services become unavailable. The inability to differentiate between a security breach and a technical lapse creates reputational risks that often extend far beyond the duration of the outage itself.

Digital certificates form the backbone of secure online communication, underpinning Transport Layer Security protocols that protect everything from mobile banking applications to backend APIs and customer data exchanges. Without valid certificates, encrypted connections fail, systems stop responding, and digital services can shut down within minutes. Abdulsalam emphasised that while these certificates are foundational to modern banking infrastructure, their management has not evolved at the same pace as the increasingly complex and distributed environments in which they operate, leaving institutions exposed to avoidable disruptions.

The challenge is further intensified by the steady reduction in certificate validity periods. What previously lasted several years has already been reduced to just over a year, with the industry now moving towards a 90-day standard driven by browser vendors and certificate authorities seeking to enhance security. While this shift reduces the long-term risk of compromised keys, it significantly increases operational demands. Large financial institutions managing thousands of certificates must now execute tens of thousands of renewals annually across cloud platforms, legacy systems, microservices, and third-party integrations, many of which are deployed across decentralised teams with varying levels of oversight.

Drawing from his experience within enterprise security environments, Abdulsalam noted that the most significant risks often stem from gaps in visibility rather than lapses in execution. “The certificate that expires unnoticed is rarely the one the team forgot. It is the one the team did not know existed,” he said. He explained that undocumented assets, overlooked integrations, and inherited systems frequently fall outside formal tracking mechanisms, creating hidden vulnerabilities that only surface when services fail. He added that security teams, already burdened with threat detection, compliance, and incident response responsibilities, often lack the capacity to continuously monitor certificate lifecycles without automated support.

The issue has gained increased regulatory urgency following the implementation of operational resilience frameworks by UK authorities, including the Financial Conduct Authority and the Prudential Regulation Authority in March 2025. These frameworks require institutions to identify, map, and safeguard critical services against foreseeable disruption. Abdulsalam, who is also the creator of CertPulse, DefenceIQ, and PrepIQ, platforms focused on certificate lifecycle management, fraud intelligence, and cyber preparedness, stressed that certificate-related outages fall squarely within this category. He noted that as the industry continues to prioritise high-profile cyber threats, organisations must not overlook foundational risks, warning that a single expired certificate can rapidly escalate into a large-scale outage affecting customers, operations, and institutional trust, with consequences that may take months to fully resolve.