I know your customers' passwords

Go to your ESP customer login page and use “View Source” to look at the HTML (under “Page” on Internet Explorer, “Tools->Web Developer” on Firefox, and “View” on Safari).
Go on, I’ll wait.
Search for the word autocomplete. If it says something like autocomplete=”off” then your web developers have already thought about this security issue. If it doesn’t, then you might have a serious security problem.
What’s going on here? You’ve probably noticed that when you’re filling in a web form your browser will often offer to fill in data for you once you start typing. This feature is supported by most modern browsers and it’s very convenient for users – but it works by recording the contents of the form in the browser, including the username and password.
As a bad guy that’s very interesting data. I can take some off-the-shelf malware and configure it with the URLs of a bunch of ESP login pages. Then I just need to get that malware installed on your customers desktops somehow. A targeted web drive-by malware attack, maybe based on targeted hostile banner ads is one approach, but sending email to people likely to be ESP customers is probably more effective. Maybe I’ll use hostile email that infects the machine automatically, or – most likely – I’ll use a phishing attack, sending a plausible looking email with an attachment I’m hoping recipients will open.
Once the malware is installed it can rummage through the users browser files, looking for any data that matches the list of login pages I gave it. I just need to sit back and wait for the malware to phone home and give me a nicely packaged list of ESPs, usernames and passwords. Then I can steal that customer’s email lists and send my next phishing run through that ESP.
This isn’t a new issue – it’s been discussed since browsers started implementing autocompletion over a decade ago, and it’s been a best practice to include autocomplete=”off” for password fields or login forms for years.
How serious a risk is this for ESPs? Well, I looked at the customer login pages at several ESPs that have a history of being compromised and none of them are using autocomplete=”off”. I looked at several that haven’t been compromised that I know of, and they’re all using either autocomplete=”off” or a complex (and reasonably secure-looking) javascript approach to login. Correlation isn’t causation, but it’s fairly strong circumstantial evidence.
ESPs should fix this hole if they haven’t already. If any customers are upset about having to actually type in their password (really?) they can take a look at secure password management tools (e.g. 1Password, LastPass or KeePass).
Thanks to Tim at Silverpop for reminding me that this is a serious security hole that many ESPs haven’t plugged yet and pointing me at some of these resources.
More on passwords and application security tomorrow.

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Epsilon – Keep Calm and Carry On

There’s been a lot of media coverage and online discussion about the Epsilon data breach, and how it should be a big wake-up call to email recipients to change their behavior.
There’s also been a lot of panic and finger-pointing within the email industry about What Must Be Done In The Future. Most of the “you must do X in response to the data loss” suggestions are coming from the same people and groups who’ve been saying “you must do X” for years, and are just trying to grab the coattails of the publicity about this particular incident, though.
Not many people seem to be talking honestly about what this will really mean to an individual recipient whose email address Epsilon lost, though. I’m going to try to answer some questions I’ve seen asked realistically, rather than with an eye to forwarding an agenda.
1. Who are Epsilon?
Epsilon are an Email Service Provider, or ESP. That means that they handle sending email on behalf of other companies. If you’re on a company’s mailing list – you’re getting regular newsletters or special offers or any sort of email advertising – the odds are very good that the company isn’t sending you that email themselves. Instead they’re probably contracting with one of hundreds of ESPs to send the email for them. This is a good thing, as sending email to a lot of people “properly” such that it’s delivered to them in a timely fashion, it’s sent only to people who want it and so on is quite difficult to do well and any ESP you choose is likely to be better at it than a typical company trying to start sending that bulk mail themselves.
2. What happened at Epsilon?
The what is pretty simple – somebody stole a list of names and email addresses of people who were being sent email via Epsilon. Nobody outside of Epsilon and law enforcement really know the details of how it was done, though lots of people are speculating about it.
3. Is this identity theft? Do I need to check my credit rating and so on?
No, it’s not something that’s going to lead to identity theft. All that was stolen was your name, your email address and some of the companies who send you email. Your postal address, credit card numbers, social security numbers and so on aren’t at risk, even if you’ve given those to the companies who are sending you email. The only information those companies passed to Epsilon were your name and email address, nothing more, so that’s all that was stolen.
4. Is this common?
Yes, it happens all the time. I use tagged email addresses when I give them to a company, and I’ve done so fairly consistently for the better part of two decades. That lets me track when email addresses are leaked, by who and to whom. Email addresses you give to a company leak to spammers all the time. That’s true for huge companies, tiny one-woman companies, tech-savvy companies, everyone.
5. How do email addresses leak from companies to spammers?
There are a lot of ways

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Epsilon: Calm and Cool Tempered

Stefano over at emailmarketingblog.it translated our blog post about Epsilon into Italian: Epsilon e la sicurezza dei dati sensibili: calma e sangue freddo.

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First spam to Epsilon leaked address

This morning I received the first two spams to the address of mine that was compromised during the Epsilon compromise back in April. Actually, I received two of them. One was the “standard” Adobe phish email. The other was similar but referenced Limewire instead of Adobe.

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