Earlier this month, Sendgrid reported that a customer account was compromised and used for phishing. At the time Sendgrid thought that it was only a single compromise. However, they did undertake a full investigation to make sure that their systems were secure.
Today they released more information about the compromise. It wasn’t simply a customer account, a Sendgrid employee’s credentials were hacked. These credentials allowed the criminals to access customer data, and mailing lists. Sendgrid has a blog post listing things customers should do and describing the changes they’re making to their systems.
Last month it was Mandrill. Today it’s Sendgrid. It could be anyone tomorrow.
Security is hard, there’s no question about it. Users have to have access. Data has to be transferred. Every user, every API, every open port is a way for a bad actor to attempt access.
While it wasn’t said directly in the Sendgrid post, it’s highly likely that the employee compromise was through email. Most compromises go back to a phish or virus email that lets the attacker access the recipient’s computer. Users must be ever vigilant.
We, the email industry, haven’t made it easy for users to be vigilant. Just this weekend my best friend contacted me asking if the email she received from her bank was a phishing email. She’s smart and she’s vigilant, and she still called the number in the email and started the process without verifying that it was really from the bank. She hung up in the transaction and then contacted me to verify the email.
She sent me headers, and there was a valid DMARC record. But, before I could tell her it wasn’t a phishing email, I had to go check the whois record for the domain in question to make sure it was the bank. It could have been a DMARC authenticated email, but not from the bank. The whois records did check out, and the mail got the all clear.
There’s no way normal people can do all this checking on every email. I can’t do it, I rely on my tagged addresses to verify the mail is legitimate. If the mail comes into an address I didn’t give the sender, then it’s not legitimate – no matter what DMARC or any other type of authentication tells me. But most people don’t have access to tagged or disposable addresses.
I don’t know what the answers are. We really can’t expect people to always be vigilant and not fall for phishing. We’re just not all present and vigilant every minute of every day.
For all of you who are going to tell me that every domain should just publish a p=reject statement I’ll point out DMARC doesn’t solve the phishing problem. As many of us predicted, phishers just move to cousin and look alike domains. DMARC may protect citi.com, but citimarketingemail.com or citi.phisher.com isn’t.
We’ve got to do better, though. We’ve got to protect our own data and our customer’s data better. Email is the gateway and that means that ESPs, with their good reputations and authentication, are prime targets for criminals.

compromise • phishing • security