Image from EFF

Is e-mail OK for secret stuff?

Image by EFF

Image by EFF

Short answer: No. Slightly longer answer: Maybe, but not without additional protection.

E-mail is one of the oldest and most widely used services on Internet. It was developed during an era when we were comfortably unaware of viruses, worms, spam, e-crime and the NSA. And that is clearly visible in the architecture and blatant lack of security features. Without going deep into technical details, one can conclude that the security of plain e-mail is next to non-existing. The mail standards do by themselves not provide any kind of encryption or verification of the communicating parties’ identity. All this can be done with additional protection arrangements. But are you doing it and do you know how to?

Here’s some points to keep in mind.

  • Hackers or intelligence agencies may tap into the traffic between you and the mail server. This is very serious as it could reveal even your user ID and password, enabling others to log in to the server and read your stored mails. The threat can be mitigated by ensuring that the network traffic is encrypted. Most mail client programs offer an option to use SSL- or TLS-encryption for sent and received mail. See the documentation for your mail program or service provider. If you use webmail in your browser, you should make sure the connection is encrypted. See this article for more details. If it turns out that you can’t use encryption with your current service provider, then start looking for another one promptly.
  • Your mails are stored at the mail server. There are three main points that affect how secure they are there. Your own password and how secret you keep it, the service provider’s security policies and the legislation in the country where the service provider operates. Most ordinary service providers offer decent protection against hackers and other low-resource parties, but less protection against authorities in their home country.
  • Learn how to recognize phishing attacks as that is one of the most common reasons for mail accounts to be compromised.
  • There are some mail service providers that focus purely on secrecy and use some kind of encryption to keep messages secret. Hushmail (Canada) and Mega’s (New Zealand) planned service are good examples. Lavabit and Silent Mail used to provide this kind of service too, but they have been closed down under pressure from officials. This recent development shows that services run in the US can’t be safe. US authorities can walk in at any time and request your data or force them to implement backdoors, no matter what security measures the service provider is implementing. And it’s foolish to believe that this is used only against terrorists. It’s enough that a friend of a friend of a friend is targeted for some reason or that there is some business interest that competes with American interests.
  • The safest way to deal with most of the threats is to use end-to-end encryption. For this you need some additional software like Pretty Good Privacy, aka. PGP. It’s a bit of a hassle as both parties need to have compatible encryption programs and exchange encryption keys. But when it’s done you have protection for both stored messages and messages in transit. PGP also provides strong authentication of the message sender in addition to secrecy. This is the way to go if you deal with hot stuff frequently.
  • An easier way to transfer secret stuff is to attach encrypted files. You can for example use WinZip or 7-Zip to create encrypted packages. Select the AES encryption algorithm (if you have a choice) and make sure you use a hard to guess password that is long enough and contains upper and lowercase letters, numbers and special characters. Needless to say, do not send the password to the other party by mail. Agreeing on the password is often the weakest link and you should pay attention to it. Even phone and SMS may be unsafe if an intelligence agency is interested in you.
  • Remember that traffic metadata may reveal a lot even if you have encrypted the content. That is info about who you have communicated with and at what time. The only protection against this is really to use anonymous mail accounts that can’t be linked to you. This article touches on the topic.
  • Remember that there always are at least two parties in communication. And no chain is stronger than its weakest link. It doesn’t matter how well you secure your mail if you send a message to someone with sloppy security.
  • Mails are typically stored in plaintext on your own computer if you use a mail client program. Webmail may also leave mail messages in the browser cache. This means that you need to care about the computer’s security if you deal with sensitive information. Laptops and mobile devices are especially easy to lose or steal, which can lead to data leaks. Data can also leak through malware that has infected your computer.
  • If you work for a company and use mail services provided by them, then the company should have implemented suitable protection. Most large companies run their own internal mail services and route traffic between sites over encrypted connections. You do not have to care yourself in this case, but it may be a good idea to check it. Just ask the IT guy at the coffee table if NSA can read your mails and see how he reacts.

Finally. Sit down and think about what kind of mail secrecy you need. Imagine that all messages you have sent and received were made public. What harm would that cause? Would it be embarrassing to you or your friends? Would it hurt your career or employer? Would it mean legal problems for you or your associates? (No, you do not need to be criminal for this to happen. Signing a NDA may be enough.) Would it damage the security of your country?  Would it risk the life of you or others? And harder to estimate, can any of this stuff cause you harm if it’s stored ten or twenty years and then released in a world that is quite different from today?

At this point you can go back to the list above and decide if you need to do something to improve your mail security.

Safe surfing,
Micke

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June 22, 2016
instagram bug hunter, mikko and jani, young hacker

10-Year-Old Who Took Home $10,000 Instagram Bug Bounty Visits F-Secure Labs

Mikko Hyppönen -- our Chief Research Officer and probably the most famous code warrior ever to come out of Finland -- likes to point out that he was born the same year as the internet. Jani -- the ten-year-old from Helsinki who made international news by earning Instagram's top bug bounty prize for uncovering a security flaw in the photo-sharing site -- was born a couple a years after Facebook was invented in 2004 and just four years before Instagram went online in 2010. And he's already made some history. Jani discovered a flaw in the site that would have allowed him -- or anyone -- to delete content from any user from the site, even stars with tens of millions of followers including Taylor Swift, Selena Gomez and Beyonce. Like any good white-hat hacker he didn't take advantage of the vulnerability. Instead, he reported the bug to Facebook, which now owns the app, directly. His maturity paid off. Even though he is not technically old enough to use the site according Instagram's terms and conditions, he's become the youngest person ever to win a $10,000 bug bounty, which he's used to purchase a soccer ball, a bike and other essential gear for being ten. To celebrate his feat, F-Secure Labs invited Jani to visit our headquarters for a hamburger and a tour. The visit gave our experts a chance to share their stories about how they were drawn to cybersecurity. Mikko learned to love computers from his mother who was in the industry. Päivi was guided into the field by her father and discovered that she has a passion for rooting out spam.  When Tomi was a kid striving to learn the rules of the coin games his friends played so he could hack them and win, he recognized that he didn't see the world like everyone else. Jani has already discovered the same thing. Though he finds plenty of time for school and playing with his friends, he spends 2-3 hours during his off days hunting for vulnerabilities and looking out for new bug bounty programs -- like our own -- that allow him to test his skills. How did he find the vulnerability in Instagram? First he created two accounts. He posted a comment using one account and then just using the publicly available content id number he was able to delete the comment using the other. Immediately he recognized the potential for such a flaw to be exploited. Mikko and Tomi were impressed by how Jani used Linux and Burp Suite --  a tool that pros like the analysts in our Labs use to analyze network traffic -- to help identify the bug. While he used to be interested in a career in video games, Jani says he's now thinking about becoming a cybersecurity specialist. Mikko and Tomi advised him to finish school and stay on the right side of the law. They also invited him to spend a week or two working at the Labs to see how he likes the job, when he's old enough. He's planning on taking them up on the offer, saying that F-Secure looks like a "fun and cool" place to work. Nice. We're always looking for new talent and even Mikko may retire one day.  

June 22, 2016
BY