The following are some of the top 10 biggest data breaches in the last year (from August 2020 to August 2021):

1. SolarWinds:
– Date: Discovered in December 2020.
– Impact: Compromised multiple US government agencies and private companies, including Microsoft, and potentially exposed sensitive data.

2. Facebook:
– Date: April 2021.
– Impact: Personal information of over 533 million Facebook users leaked online, including phone numbers, email addresses, and other details.

3. Ubiquiti Inc.:
– Date: January 2021.
– Impact: Unauthorized access to customer information, including names, email addresses, and encrypted passwords.

4. Juspay:
– Date: August 2020.
– Impact: Indian payment gateway, Juspay, suffered a breach that exposed customer details, card information, and more.

5. Capcom:
– Date: November 2020.
– Impact: Gaming giant Capcom faced a ransomware attack that resulted in a massive data breach, including customer data and internal files.

6. Marriott International:
– Date: Early 2020 (uncovered in March).
– Impact: Personal information of over 5 million guests exposed due to a vulnerability in their loyalty application.

7. Air India:
– Date: May 2021.
– Impact: Personal data of approximately 4.5 million Air India passengers leaked, including passport details and credit card information.

8. CD Projekt Red:
– Date: February 2021.
– Impact: Cyberattack on the game developer, CD Projekt Red, resulted in a data breach including employee and user data.

9. Mimecast:
– Date: January 2021.
– Impact: Mimecast, an email security company, suffered a cyberattack that compromised a digital certificate used to authenticate data sent between systems.

10. Accellion:
– Date: January 2021.
– Impact: Accellion, a file transfer service, experienced a cyberattack that exposed data from numerous organizations and their customers.

Please note that the impact and details of some breaches may change with time as new information becomes available.