What data telecom operators store
Telecom operators collect some of the most sensitive data sets. Personal data — name, SSN/national ID, address, identity document data, banking details. Location data — precise 24/7 subscriber location history. Call Detail Records (CDR) — who called whom, when, for how long. Internet traffic data — visited websites, data usage, activity patterns. Billing data — payment history, outstanding balances, payment methods. This dataset enables complete profiling of an individual — invaluable for intelligence agencies, criminals, and stalkers.
Threats to subscriber data
Database breaches
Attacks on operator CRM and BSS systems. Subscriber databases end up on dark web — millions of records with SSN, addresses, and phone numbers.
Unauthorized employee access
Call center agents, technicians, and analysts with excessive data access. Insider threat: selling location data, viewing billing records.
SS7/Diameter exploitation
SS7 protocol (and its successor Diameter) allows location tracking, SMS interception, and eavesdropping — if attacker gains signaling network access.
Self-care API attacks
Customer applications and portals exposing APIs. IDOR vulnerabilities, broken authentication — access to other subscribers’ data.
Law enforcement requests and abuse
Informal location data requests, data retention system abuse.
Subscriber data protection methods
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Role-based access control (RBAC) — call center agents see only data needed for service. Every access logged. Alerts on mass queries.
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Database encryption — AES-256 for data at rest, TLS 1.3 for transmission. SSN and payment card data tokenization.
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DLP — preventing subscriber data exfiltration: USB copy blocking, email monitoring, screenshot control.
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Access monitoring (UEBA) — anomaly detection: employee checking data outside hours, mass exports, VIP data access.
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SS7/Diameter security — signaling firewalls, signaling traffic anomaly monitoring, blocking unauthorized queries.
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API security — WAF, rate limiting, customer application penetration testing, OAuth 2.0 authentication.
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Data retention procedures — automatic data deletion after retention period, formal procedures for law enforcement requests.
Cybersecurity for Your Industry
Learn more about cybersecurity in your industry:
Why this matters for organizations
Subscriber data is one of the most valuable operator assets. How to protect customer databases, location data, and call history? In the context of growing cyber threats and tightening regulations (NIS2, DORA), organizations must proactively manage this security area. Failure to implement adequate safeguards can lead to data breaches, financial penalties, and reputational damage.
Best practices for implementation
Effective implementation requires several key steps:
- Risk assessment and inventory — identify assets, threats, and vulnerabilities specific to your organization.
- Policy development — document requirements, roles, and responsibilities.
- Technical controls — deploy tools and configurations proportionate to identified risks.
- Training and awareness — engage employees in protecting organizational security.
- Monitoring and continuous improvement — regularly verify effectiveness and adapt to the evolving threat landscape.
Related topics
See also:
