got this from yahoo few days ago ;
NOTICE OF DATA BREACH
We are writing to inform you about a data security issue that may involve your Yahoo account information.
A recent investigation by Yahoo has confirmed that a copy of certain user account information was stolen from our systems in late 2014 by what we believe is a state-sponsored actor. We are closely coordinating with law enforcement on this matter and working diligently to protect you.
What Information Was Involved?
The stolen user account information may have included names, email addresses, telephone numbers, dates of birth, hashed passwords and, in some cases, encrypted or unencrypted security questions and answers. Not all of these data elements may have been present for your account. The ongoing investigation suggests that stolen information did not include unprotected passwords, payment card data, or bank account information; payment card data and bank account information are not stored in the system that the investigation has found to be affected.
What We Are Doing
We are taking action to protect our users:
• We are asking potentially affected users to promptly change their passwords. You can do so now at https://att.com/emailpasswordreset
• We invalidated unencrypted security questions and answers so they cannot be used to access an account.
• We are recommending that all users who haven't changed their passwords since 2014 do so.
• We continue to enhance our systems that detect and prevent unauthorized access to user accounts.
• We are working closely with law enforcement on this matter.
Our investigation into this matter continues.
What You Can Do
We encourage you to follow these security recommendations:
• Change your password and security questions and answers for any other accounts on which you used the same or similar information used for your Yahoo account.
• Review your accounts for suspicious activity.
• Be cautious of any unsolicited communications that ask for your personal information or refer you to a web page asking for personal information.
• Avoid clicking on links or downloading attachments from suspicious emails.
For More Information
For more information about this issue please see the FAQs below.
Protecting your information is important to us and we work continuously to strengthen our defenses against the threats targeting our industry.
Chief Information Security Officer
Frequently Asked Questions
1. What happened?
A recent investigation by Yahoo has confirmed that a copy of certain user account information was stolen from our network in late 2014 by what we believe is a state-sponsored actor. We are working closely with law enforcement authorities and notifying potentially affected users of ways they can further secure their accounts.
2. Was my account affected?
We are notifying potentially affected users by email and posting additional information to our website. Additionally, we are asking potentially affected users to promptly change their passwords and adopt alternate means of account verification.
3. Is the state-sponsored actor still in Yahoo's network?
The ongoing investigation has found no evidence that the state-sponsored actor is currently in Yahoo's network.
4. What information was stolen?
The stolen user account information may have included names, email addresses, telephone numbers, dates of birth, hashed passwords (the vast majority with bcrypt) and, in some cases, encrypted or unencrypted security questions and answers. The ongoing investigation suggests that stolen information did not include unprotected passwords, payment card data, or bank account information; payment card data and bank account information are not stored in the system that the investigation has found to be affected.
5. What is a "hashed password"?
Hashing is a one-way mathematical function that converts an original string of data into a seemingly random string of characters. As such, passwords that have been hashed can't be converted into the original plain text password.
6. What additional steps can I take to protect my information?
Although the affected account information did not include unprotected passwords, payment card data, or bank account information, we encourage you to remain vigilant by reviewing your account statements and monitoring your credit reports. Below is contact information for the three consumer reporting agencies from which you can obtain a credit report.
Equifax Equifax Credit Information Services, Inc.
P.O. Box 740241
Atlanta, GA 30374 1-800-525-6285 http://www.equifax.com
Experian Experian Inc.
P.O. Box 9554
Allen, TX 75013 1-888-397-3742 http://www.experian.com
TransUnion TransUnion LLC
P.O. Box 2000
Chester, PA 19022-2000 1-800-680-7289 http://www.transunion.com
You also may wish to place a "security freeze" (also known as a "credit freeze") on your credit file. A security freeze is designed to prevent potential creditors from accessing your credit file at the consumer reporting agencies without your consent. There may be fees for placing, lifting, and/or removing a security freeze, which generally range from $5-$20 per action. Unlike a fraud alert, you must place a security freeze on your credit file at each consumer reporting agency individually. For more information on security freezes, you may contact the three nationwide consumer reporting agencies or the FTC as described above. As the instructions for establishing a security freeze differ from state to state, please contact the three nationwide consumer reporting agencies to find out more information.
The consumer reporting agencies may require proper identification prior to honoring your request. For example, you may be asked to provide:
• Your full name with middle initial and generation (such as Jr., Sr., II, III)
• Your Social Security number
• Your date of birth
• Addresses where you have lived over the past five years
• A legible copy of a government-issued identification card (such as a state driver's license or military ID card)
• Proof of your current residential address (such as a current utility bill or account statement)
You have the right to obtain a police report and request a security freeze as described above. The consumer reporting agencies may charge you a fee of up to $10 to place a security freeze on your account, and may require that you provide certain personal information (such as your name, Social Security number, date of birth, and address) and proper identification (such as a copy of a government-issued ID card and a bill or statement) prior to honoring your request for a security freeze. There is no charge, however, to place, lift or remove a security freeze if you have been a victim of identity theft and you provide the consumer reporting agencies with a valid police report.
For U.S. residents, you can contact the FTC to learn more about protecting your personal information. The contact information for the FTC is below:
Federal Trade Commission
Consumer Response Center
600 Pennsylvania Avenue, NW
Washington, DC 20580
For Rhode Island residents, you may obtain information about protecting your personal information from the Rhode Island Office of the Attorney General at:
Rhode Island Office of the Attorney General
Consumer Protection Unit
150 South Main Street
Providence, RI 02903