In June 2024, Citibank experienced a security incident that was reported in an article. The incident involved unauthorized access to customer records, exposing sensitive information. Attackers exploited a vulnerability in the bank's web systems, taking advantage of a flaw.
How many accounts were compromised?
The breach impacted data related to approximately 350,000 individuals.
What data was leaked?
The data exposed in the breach included customer names, account numbers, and contact information.
How was Citibank hacked?
Hackers gained access to over 350,000 Citibank customer records by exploiting a vulnerability in the bank's web application and APIs, specifically through parameter tampering. The breach was exacerbated by a flaw in the app's business logic and predictable account numbers, allowing the attackers to automate the theft of large continuous numbers without having to search for specific numbers online. The exact methods and tools used by the hackers remain unclear.
Citibank's solution
In response to the hack, Citibank's specific actions remain unclear. However, it is suggested that implementing random UID's instead of incremental IDs for record identification in databases and continuously scanning & validating access-control logic on all endpoints could help protect against similar attacks in the future. The exact measures taken by Citibank to secure its platform and prevent future incidents are not detailed in the available information.
How do I know if I was affected?
Citibank's outreach to affected users is not explicitly mentioned in the available sources. However, if you are a Citibank customer and have not received any notification, you may visit Have I Been Pwned to check if your credentials have been compromised in the breach.
What should affected users do?
In general, affected users should:
Change Your Password: Immediately update your password for the breached account. Make sure the new password is strong and unique, not previously used on any other platform.
Reset Passwords for Other Accounts: If you've used the same or similar passwords for other online accounts, reset those as well. This is crucial as attackers often try using stolen passwords on multiple sites.
Enable Two-Factor Authentication (2FA): Activate 2FA on the breached account and any other important online accounts to significantly reduce the risk of unauthorized access.
Monitor Your Accounts: Keep an eye on your accounts for any suspicious activity and report it to the respective platform or financial institution immediately.
For more specific help and instructions related to Citibank's data breach, please contact Citibank's support directly.
Where can I go to learn more?
If you want to find more information on the Citibank data breach, check out the following news articles:
