T-Mobile US, Inc. (TMUS) shares climbed 1.95% to $159.49, adding $3.05 during the trading session. The stock recovered from morning losses and maintained an upward trajectory throughout the afternoon. The move came as the wireless carrier published a new cybersecurity report detailing substantial improvements in network protection, employee security, and customer account safety. For telecom operators, whose networks carry sensitive customer communications, published security metrics have become a tangible way to demonstrate resilience in a sector facing growing threats from nation-state attackers and financially motivated criminals.

Report Outlines Overhaul of Security Operations

T-Mobile released the report, Advancing Cybersecurity at T-Mobile, outlining changes to its security operations and their measurable results. The publication describes how the company rebuilt its cybersecurity program while maintaining uninterrupted wireless services and business operations, and how it responded to growing threats from nation-state attackers and financially motivated criminals.

Over a recent 12-month period, the company recorded a 37% increase in attempted intrusions. At the same time, credential-based attack attempts declined 35%, a shift the report says indicates changes in the methods used by cybercriminals. Phishing-related credential compromises among employees fell by more than 99% following extensive security improvements.

As part of the overhaul, T-Mobile replaced employee passwords with phishing-resistant FIDO2 hardware security keys and now operates a passwordless system across nearly 100% of its workforce. Employees must also complete identity verification using selfies and government-issued identification before receiving system credentials. The shift addresses a common weakness, since passwords remain a frequent entry point for phishing campaigns across industries.

SIM Swap Attacks Down More Than 99% Since 2022

T-Mobile reported a reduction of more than 99% in successful SIM swap attacks since 2022. The company introduced additional authentication measures, including biometric identity verification, SIM Protection, and Port-Out Protection. These measures strengthen account security and reduce opportunities for unauthorized access to customer mobile services.

SIM swap attacks are widely considered among the most damaging forms of consumer fraud: by getting a victim's phone number transferred to a device they control, attackers can intercept calls, texts, and the one-time passcodes that protect email, banking, and other online accounts. Reducing successful attacks to this degree narrows a well-known pathway to account takeover.

The report also detailed T-Mobile's response to the Salt Typhoon cyberattack in late 2024. The state-sponsored group targeted American telecommunications providers through sophisticated methods involving third-party infrastructure. T-Mobile's layered security systems contained the attackers before they could access sensitive customer information. The episode reflects broader industry pressure, as telecommunications networks are treated as critical infrastructure and remain high-value targets for espionage-driven operations.

T-Mobile deployed its hybrid zero-trust security framework across its workforce within six months. The platform has blocked more than six million online threats since its launch, and network-level protections now cover all T-Mobile customers across calls, text messages, and internet browsing.

Expanded Security Investments and Future Threat Preparation

Customer protection remains another major component of the company's cybersecurity strategy. Since March 2017, Scam ID and Scam Block have helped protect customers against more than 160 billion unwanted calls. During 2025, T-Mobile blocked nearly three billion scam and spam messages before delivery.

The company has also broadened its cybersecurity operations through employee training and dedicated threat response systems. Its workforce completed more than 200,000 cybersecurity training sessions during 2025, and the Cyber Defense Center combines threat monitoring, digital forensics, and incident response within a single operational structure.

Looking ahead, T-Mobile plans to strengthen defenses against artificial intelligence-enabled fraud, automated identities, and quantum computing threats. The company also works with CISA, C2 ISAC, and CTIA to improve telecommunications security across the industry. The report further highlights a bug bounty program that has received more than 1,400 valid submissions from security researchers worldwide. With these metrics now public, the reported figures give customers and researchers a baseline for tracking whether the carrier's security gains hold as attack techniques continue to evolve.