Rossander’s Security Reader

A couple of years ago, I taught a class on reducing email bloat and “taking back control of your inbox”. It was a fun class based on the lessons in The Hamster Revolution. If you haven’t read the book, it’s well worth the time.

CIO magazine recently published an article on keeping email from ruining your vacation. The same basic principle applies. That is, if you write well-crafted, professional, on-topic emails, the people you talk with will start to write more professionally back to you.

The CIO article goes on with some other suggestions to take advantage of new technologies to help people either remember that you’re on vacation or to help themselves while you’re gone.

• Filesharing is good. Take the time during the year to set up better collaboration and it will pay dividends when you need some time away.
• Minimize constant email exchanges. They’re too transient and hard to file. They don’t create the institutional knowledge that a wiki or well-designed fileshare can. And if it’s a really complicated or sensitive issue, email may not be the best choice in the first place. Some things should be sorted out in person.
• If you can manage a wiki, they’re great tools.
• Updating your status on Facebook, Twitter or LinkedIn will let everyone know where you are but I really do not recommend it. The updates are helpful for your customers and friends but they also paint a big red target on your house while you’re gone. You’re advertising that your house is unattended and vulnerable.

Take some time up front so that you can really be on vacation.

NPR ran an interesting story this morning about President Obama’s dispute with his own information security team about whether or not he would keep his Blackberry. The President won and will be keeping it. An expert from SANS.org blasted that decision, saying that the device was inherently insecure and talking about all the special modifications that he thinks the Secret Service will make to protect it.

He went on to describe some of the attacks that can be made against a Blackberry. For example, with the right set of instructions, the phone’s microphone can be turned on without it being obvious. Someone can listen in on your conversation right through your phone. For another example, the email server can be hacked or the cell phone transmissions intercepted.

All those arguments are entirely true. And they are real reasons for the President’s security team to be worried. After all, the President really does have nuclear secrets that he needs to protect. And there are all sorts of people who would love to break into his messages and who will devote immense resources to do so.

But the story was edited in a way that implied that Blackberrys are inherently insecure for the rest of us, too. Much as I like to think highly of my own self-importance, there just aren’t that many people out there who are attacking me and they certainly won’t be devoting the same kind of resources to breaking into my phone messages.

That said, you should always remember that Blackberrys run email and email is an inherently insecure system. (You can run an encrypted email program on top of regular email but PDAs don’t support that well today.) As a matter of general practice, never say anything in email that you wouldn’t want to see on the front page of the newspaper tomorrow.

The same goes for your cell phone conversations. They are a bit better protected than the SANS guy implied but there are still ways to intercept and decrypt them. Most importantly, most cell phone intercepts require the hacker to be physically close. For those of us who are not heads of state, this dramatically reduces the risk. But you still shouldn’t say anything on a cell phone that you wouldn’t say in public.

Lastly, you should keep up to date on PDA protections. There are some new viruses that target mobile phones. The major phone companies are starting to include anti-virus on their phones. If you have it, make sure you don’t turn it off. If you don’t have it, look for that capability when you next renew your phone contract. Keep using your Blackberry but use it safely.

Back by popular demand, this "encore tip" is a reminder to be especially professional in your email communications. Please share this seasonal message with your co-workers. (This Tip was first run in October 2006.)

Halloween is a time for scary stories – tales of vampires and ghouls rising from the dead to terrify innocents – a time when things that you thought were dead and buried come back to haunt you.

Unfortunately, the analogy between badly written email and the undead is sometimes all too appropriate. A hasty word can return to haunt you long after you hit the send button and thought the conversation was over. Careers have been destroyed, money lost and relationships ruined when an email returned from beyond.

Americans have a bad habit of treating email very casually – as an extension of our last phone conversation or a continuation of the chat in the hallway. We assume that the message is private and that recipient will understand the context and correctly interpret our tone.

In fact, email is more like a postcard – anyone can read it while it’s in transit^† and any of the recipients can save it, forward it or post it to the internet. Electronic copies can remain in archives and electronic message hubs all over the Internet – places that neither the sender nor the recipient can control. Emails can be subpoenaed and forced into the public record. You have no right of privacy in your email, either sent or received. When you write an email, you must assume that it will be read by an unknown and unforeseen audience.

That unknown audience will assume that you carefully crafted and wordsmithed your message (or, if not, that the hurried email is evidence of the writer’s “real state of mind”). They will not believe that you were “just joking” and won’t care that you were trying to dash off a quick note. They will interpret the tone according to their own preconceptions.

Always assume that anything you write will come out at the worst possible time and in the worst possible light. Be professional in your email. Include enough context that the unforeseen reader understands the message. Be personable yet professional in tone. (In particular, never use sarcasm in email.) Never write anything that you would be embarrassed to see on the front page of tomorrow’s newspaper.

Remember, email can come back to haunt you.

^† Footnote: The comment that “anyone can read [your email] while it’s in transit” is less true if you have email encryption with your business partners but your words can still be saved, forwarded or otherwise sent outside your control. Please don’t assume that email encryption will protect you from sloppy wording.

Spam filters are getting better every year. They have to so they can keep up with the ever-increasing flood of spam. But no matter how good the filters get, some spam will always leak through. More worrying, some fraction of good messages will be inappropriately tagged as spam and lost. And depending on how your respective spam filters are set, your reader may never even know that the message was attempted nor you that the message was rejected.

A while back, we wrote a tip about "how not to look like a phish". I’ve wanted to write the companion article about not accidentally tripping the spam filters for several years now. I resisted because the rapid change in spammer tactics makes any list obsolete even before it hits the page. It will also never be a definitive list – the anti-spam vendors are justifiably worried about giving the spammers a roadmap showing how to bypass their filters. Nevertheless, there are some general rules worth discussing.

• Your subject line is important. A blank subject line (or, worse, a subject line that is ambiguous and generic like "Hi" or "I love you") will almost certainly get your message tagged as spam. A good subject line is also a courtesy to your readers, helping them to more quickly prioritize their inboxes and give your email the attention it deserves.
• Mailing to lots of people at once will increase the odds of being tagged as spam. (This is a problem for the publishers of legitimate email newsletters with large distribution lists like, say, these tips.)
• Use a company-issued email address. Sending from a free email account like yahoo.com or gmail will increase the odds of getting tagged.
• Avoid common spam words like "cheap" and the V- word (rhymes with the famous waterfall). That sometimes means completely avoiding certain topics (which can be quite difficult, especially in a newsletter like this one where we are discussing spammer tactics) but more often means avoiding flowery, inflammatory or overly-promotional language. In particular, avoid all caps and multiple exclamation marks.
• Avoid images, fancy graphics and html code in your email. Hackers and spammers hide things in those glossy "enhancements". The simpler your message, the more likely it is to get through unmolested.
• SPELL-CHECK! Spammers are getting much better at the use of grammatically correct English but bad spelling is still a surprisingly good filter for spam.
• If you are sending a newsletter, always include your real contact information and a working set of “unsubscribe” instructions at the bottom of the message. This won’t actually help you get past the spam filters – too many spammers just include fraudulent unsubscribe options in their messages – but it is the law.
• Try to keep your message under two megabytes including embedded pictures and attachments. This isn’t strictly a spam-filtering rule but many mail servers use a 2 meg/message limit to keep any one message from tying up the lines.

Finally, if you don’t get an answer in a reasonable amount of time, follow up on your message. No matter what you do or how good the filters get, some false positives will always exists. The person might be ignoring you but it’s more likely that they never got the message.

For several years now, we’ve been telling everyone that email is a postcard – everything in the message is exposed to anyone who wants to read the message as it flashes by. A couple of companies have figured out how to solve this problem and their solutions are finally hitting critical mass. If you have a secure mail solution, you can finally put your message in an ‘envelope’ and keep outsiders from reading it.

The problem is that we’ve also told you as a reader to delete any message that appears suspicious or that asks you to click through some “convenient” link. The ‘envelope’ around a secured message looks a lot like a phish. (See “How it works” below.)

Here are some tips on telling the difference between a secure mail message and a spam or phish.

• In a legitimate message, you will still be able to read the subject line and the sender. If you are not expecting a message from that sender, be suspicious.
• Once you start working with a business partner who uses a secure mail system, all secure messages from that company should look basically the same. If the logo, the layout or the text look different, be suspicious.
• A legitimate message will take you to the sender’s website to verify your login. A phish will try to take you someplace else to steal your password. If the message alleges to come from someone at redcross.org but the link is trying to take you to yahoo.com, be suspicious.
  Reminder: The only part of the domain that matters is the part immediately before the top-level domain (.com, .org, etc). Ignore everything to the left or right of the dots. In the link voltage-pp-0000.westfieldgrp.com/mail/32/, only ‘westfieldgrp’ matters for verifying the legitimacy of the message. The rest is set up by the company’s IT department to point to specific places within the company’s domain.
• Legitimate messages are written by professionals. Scam messages want to panic you into acting without thinking and often use phrases like “URGENT” and “log in now or your account will be closed”. If the language seems inflammatory, be suspicious.

If you are suspicious, call the sender and confirm the message. Please do not just delete these messages, though. There’s a fair chance they are legitimate and you wouldn’t want to lose good messages.

How it works
There are several ways to put your message in the secure ‘envelope’.
One technique doesn’t actually put the content in email at all. What you really send is a placeholder saying “You have a message waiting. Please sign in at my website to read it.” The message content stays on the sender’s webserver and never actually travels by email. Some large financial and medical institutions use this kind of secure messaging.
The other way is to pull the content off the message, encrypt it and reattach it to the message. The content travels by email and but can’t be read except by someone who knows the password. (If you don’t already have a password set up, you will be asked to verify your identity and create one.)

A third technique is Transport Layer Security (TLS), a method that protects the message from one email server to another. This requires some setup between the two companies but is otherwise invisible to both the sender and the reader. These messages can’t be easily mistaken for a phish so we won’t discuss them in this tip.
An example of that second kind of ‘envelope’ – the encrypted attachment solution – is shown below.