Security Magazine logo
search
cart
facebook twitter linkedin youtube
  • Sign In
  • Create Account
  • Sign Out
  • My Account
Security Magazine logo
  • NEWS
    • Security Newswire
    • Technologies & Solutions
  • MANAGEMENT
    • Leadership Management
    • Enterprise Services
    • Security Education & Training
    • Logical Security
    • Security & Business Resilience
    • Profiles in Excellence
  • PHYSICAL
    • Access Management
    • Fire & Life Safety
    • Identity Management
    • Physical Security
    • Video Surveillance
    • Case Studies (Physical)
  • CYBER
    • Cybersecurity News
    • More
  • BLOG
  • COLUMNS
    • Career Intelligence
    • Cyber Tactics
    • Cybersecurity Education & Training
    • Leadership & Management
    • Security Talk
  • EXCLUSIVES
    • Annual Guarding Report
    • Most Influential People in Security
    • The Security Benchmark Report
    • Top Guard and Security Officer Companies
    • Top Cybersecurity Leaders
    • Women in Security
  • SECTORS
    • Arenas / Stadiums / Leagues / Entertainment
    • Banking/Finance/Insurance
    • Construction, Real Estate, Property Management
    • Education: K-12
    • Education: University
    • Government: Federal, State and Local
    • Hospitality & Casinos
    • Hospitals & Medical Centers
    • Infrastructure:Electric,Gas & Water
    • Ports: Sea, Land, & Air
    • Retail/Restaurants/Convenience
    • Transportation/Logistics/Supply Chain/Distribution/ Warehousing
  • EVENTS
    • Industry Events
    • Webinars
    • Solutions by Sector
    • Security 500 Conference
  • MEDIA
    • Interactive Spotlight
    • Photo Galleries
    • Podcasts
    • Polls
    • Videos
      • Cybersecurity & Geopolitical Discussion
      • Ask Me Anything (AMA) Series
  • MORE
    • Call for Entries
    • Classifieds & Job Listings
    • Newsletter
    • Sponsor Insights
    • Store
    • White Papers
  • EMAG
    • eMagazine
    • This Month's Content
    • Advertise
  • SIGN UP!

Big Business Customer Emails Compromised

Biggest Security Breach Ever? Third Party of Big Businesses Hacked

Reputations Can Be Harmed

April 5, 2011

The names and e-mails of customers of Citigroup Inc and other large U.S. companies, as well as College Board students, were exposed in a massive and growing data breach after a computer hacker penetrated online marketer Epsilon. In what could be one of the biggest such breaches in U.S. history, a diverse number of companies that did business with Epsilon stepped forward over the weekend of April 3 to warn customers some of their electronic information could have been exposed. Drugstore Walgreen, Video recorder TiVo Inc, credit card lender Capital One Financial Corp, and teleshopping company HSN Inc all added their names to a list of targets that also includes some of the nation’s largest banks. The names and electronic contacts of some students affiliated with the U.S.-based College Board which represents some 5,900 colleges, universities and schools were also potentially compromised. No personal financial information such as credit cards or social security numbers appeared to be exposed, according to the company statements and e-mails to customers. Epsilon, an online marketing unit of Alliance Data Systems Corp, said April 1 that a person outside the company hacked into some of its clients’ customer files. The vendor sends more than 40 billion e-mail ads and offers annually, usually to people who register for a company’s Web site or who give their e-mail addresses while shopping. Law enforcement authorities are investigating the breach, though it was unclear April 3 how many customers or students had been exposed. Epsilon is also looking into what went wrong.

Share This Story

Blog Topics

Security Blog

On the Track of OSAC

Blog Roll

Security Industry Association

Security Magazine's Daily News

SIA FREE Email News

SDM Blog

Manage My Account
  • Security Newsletter
  • eMagazine Subscriptions
  • Manage My Preferences
  • Online Registration
  • Mobile App
  • Subscription Customer Service

More Videos

Popular Stories

Man on laptop

Healthcare Executives Face a New Era of Personal Risk

Man walking with briefcase

The Rising Tide of Executive Protection: Corporations Ramp Up Security in an Era of Heightened Threats

Stadium

Physical Security in Global Arenas: How AI Improves Security at Scale

Head in front of monitors

Ransomware Response: How Businesses Regain Control Under Pressure

Chatbot prompt screen

8 in 10 AI Chatbots Likely to Help Plan Attacks, Hate Crimes

SEC 2026 Benchmark Banner
SEC 2026 Benchmark Banner

Events

April 21, 2026

The Blind Spot in Enterprise Security: Managing Workforce Risk Post-Hire

Organizations continuously monitor their networks and systems for risk, yet the people with legitimate access are often the least monitored part of the model. Discover a Workforce Risk Intelligence Framework that adds a dedicated layer focused on workforce risk.

April 30, 2026

Building a Campus-Wide Culture of Security and Shared Responsibility

In today’s higher education environment, where institutions face evolving and multifaceted incidents, safety must be embedded into the fabric of campus culture. Learn strategies for generating collective buy-in from faculty, staff, students and senior leadership. 

View All Submit An Event

Products

Security Culture: A How-to Guide for Improving Security Culture and Dealing with People Risk in Your Organisation

Security Culture: A How-to Guide for Improving Security Culture and Dealing with People Risk in Your Organisation

See More Products
SEC 2026 Top Cybersecurity Leaders
×

Sign-up to receive top management & result-driven techniques in the industry.

Join over 20,000+ industry leaders who receive our premium content.

SIGN UP TODAY!
  • RESOURCES
    • Advertise
    • Contact Us
    • Store
    • Want More
  • SIGN UP TODAY
    • Create Account
    • eMagazine
    • Newsletter
    • Customer Service
    • Manage Preferences
  • SERVICES
    • Marketing Services
    • Reprints
    • Market Research
    • List Rental
    • Survey/Respondent Access
  • STAY CONNECTED
    • LinkedIn
    • Facebook
    • YouTube
    • X (Twitter)
  • PRIVACY
    • PRIVACY POLICY
    • TERMS & CONDITIONS
    • DO NOT SELL MY PERSONAL INFORMATION
    • PRIVACY REQUEST
    • ACCESSIBILITY

Copyright ©2026. All Rights Reserved BNP Media, Inc. and BNP Media II, LLC.

Design, CMS, Hosting & Web Development :: ePublishing