Vulnerabilities at AT&T, T-Mobile and Sprint Could Have Exposed Customer Data

Vulnerabilities at AT&T, T-Mobile and Sprint Could Have Exposed Customer Data

Last week was not a good week for telecommunications companies.

Security researchers have uncovered security flaws with systems at AT&T, Sprint and T-Mobile that could have left customer data accessible to bad actors.

The flaws impacting AT&T and T-Mobile were first reported. In T-Mobile's case, an "engineer mistake" between Apple's online storefront and T-Mobile's account validation API allowed for an unlimited number of attempts on an online form, which would allow a hacker to use commonly-available tools to guess an account PIN or the last four digits in a customer's social security numbers, in what's called a brute-force attack. The vulnerability has since been fixed.

A similar problem occurred with phone insurance company Asurion and its AT&T customers. An online form would allow anyone with a customer's phone number to access a form that allowed them unlimited guesses to guess a customer's passcode, leaving it vulnerable to another brute-force attack. The vulnerability has since been fixed.

At Sprint, security researchers were able to access an internal portal because of a "weak, easy-to-use usernames and passwords," compounded with the lack of two-factor authentication. Once in, the researcher was reportedly able to access customer account information for Sprint, Boost Mobile, and Virgin Mobile. The researcher also reported that anyone who gained access could make changes to customer accounts and that customers PINs could be brute-forced.

A Sprint spokesperson confirmed the vulnerability to TechCrunch, and noted that it didn't believe that any customers were affected by the vulnerability. The spokesperson said they were working to fix the issue.

About the Author

Sydny Shepard is the Executive Editor of Campus Security & Life Safety.

Featured

  • The Future of Access Control: Cloud-Based Solutions for Safer Workplaces

    Access controls have revolutionized the way we protect our people, assets and operations. Gone are the days of cumbersome keychains and the security liabilities they introduced, but it’s a mistake to think that their evolution has reached its peak. Read Now

  • A Look at AI

    Large language models (LLMs) have taken the world by storm. Within months of OpenAI launching its AI chatbot, ChatGPT, it amassed more than 100 million users, making it the fastest-growing consumer application in history. Read Now

  • First, Do No Harm: Responsibly Applying Artificial Intelligence

    It was 2022 when early LLMs (Large Language Models) brought the term “AI” into mainstream public consciousness and since then, we’ve seen security corporations and integrators attempt to develop their solutions and sales pitches around the biggest tech boom of the 21st century. However, not all “artificial intelligence” is equally suitable for security applications, and it’s essential for end users to remain vigilant in understanding how their solutions are utilizing AI. Read Now

  • Improve Incident Response With Intelligent Cloud Video Surveillance

    Video surveillance is a vital part of business security, helping institutions protect against everyday threats for increased employee, customer, and student safety. However, many outdated surveillance solutions lack the ability to offer immediate insights into critical incidents. This slows down investigations and limits how effectively teams can respond to situations, creating greater risks for the organization. Read Now

  • Security Today Announces 2025 CyberSecured Award Winners

    Security Today is pleased to announce the 2025 CyberSecured Awards winners. Sixteen companies are being recognized this year for their network products and other cybersecurity initiatives that secure our world today. Read Now

New Products

  • AC Nio

    AC Nio

    Aiphone, a leading international manufacturer of intercom, access control, and emergency communication products, has introduced the AC Nio, its access control management software, an important addition to its new line of access control solutions.

  • Compact IP Video Intercom

    Viking’s X-205 Series of intercoms provide HD IP video and two-way voice communication - all wrapped up in an attractive compact chassis.

  • EasyGate SPT and SPD

    EasyGate SPT SPD

    Security solutions do not have to be ordinary, let alone unattractive. Having renewed their best-selling speed gates, Cominfo has once again demonstrated their Art of Security philosophy in practice — and confirmed their position as an industry-leading manufacturers of premium speed gates and turnstiles.