OpenSea, the largest NFT marketplace, has warned of a data breach that its email delivery service provider—Customer.io—suffered, which could likely impact all its users.
According to OpenSea, an employee of Customer.io misused their employee access to download and share the email addresses of OpenSea users with an unauthorized external party.
This includes emails for signing up and subscribing to OpenSea’s newsletter.
Cory Hardman, the head of Security at OpenSea stated:
We recently learned that an employee of Customer.io, our email delivery vendor, misused their employee access to download and share email addresses – provided by OpenSea users and subscribers to our newsletter – with an unauthorized external party. If you have shared your email with OpenSea in the past, you should assume you were impacted. We are working with Customer.io in their ongoing investigation, and we have reported this incident to law enforcement.
Please stay vigilant about your email practices, and be alert for any attempt to impersonate OpenSea via email
Because the data compromise included email addresses, there may be a heightened likelihood for email phishing attempts.
Please be aware that malicious actors may try to contact you using an email address that looks visually similar to the official email domain, ‘opensea.io’ (such as ‘opensea.org’ or some other variation).
While safe email practices are always important, OpenSea strongly recommend that you follow the guidelines listed below and treat any future emails that appear to be from OpenSea carefully.
Safety Recommendations:
- Be cautious of phishing emails from addresses trying to impersonate OpenSea. OpenSea will ONLY send you emails from the domain: ‘opensea.io.’ Please do not engage with any email claiming to be from OpenSea that does not come from this email domain.
- Never download anything from an OpenSea email. Authentic OpenSea emails do not include attachments or requests to download anything.
- Check the URL of any page linked in an OpenSea email. We will only include hyperlinks to ‘email.opensea.io.’ URLs. Make sure that ‘opensea.io’ is spelled correctly, as it’s common for malicious actors to impersonate URLs by shuffling letters.
- NEVER share or confirm your passwords or secret wallet phrases. OpenSea will never prompt you to do this – in any format.
- NEVER sign a wallet transaction prompted directly from an email. OpenSea emails will never contain links which directly prompt you to sign a wallet transaction. Never sign a wallet transaction that doesn’t list the origin of https://opensea.io if you were led there by email.