Case Study: UK Mobile Network Operator achieves stronger legacy network resilience with Fox-IT telecom security testing

UK mobile network operator reduces legacy telecom exposure with Fox-IT

A UK mobile network operator faced significant security challenges due to its reliance on a complex mix of legacy 2G, 3G, and 4G infrastructure. These systems, which supported critical services like voice, SMS, and roaming, had uneven security controls, creating visibility gaps and exposing the operator to risks like fraud, interception, and nationwide service disruption. To address this, the operator partnered with Fox-IT for a telecom-specific Legacy Network Security Testing Programme.

Fox-IT delivered a structured solution involving legacy network security assessments, access model reviews, threat-led testing, and monitoring evaluations. This helped the operator achieve greater cyber risk visibility, reduce high-risk exposures, and strengthen segmentation and authentication. The results included a reduced likelihood of catastrophic telecom-layer compromise and significantly improved resilience for its national mobile services.