Showing posts with label scam. Show all posts
Showing posts with label scam. Show all posts

Friday, 9 October 2009

Web Passwords

Passwords can be a pain. There are thousands of websites across the Internet that require passwords. Traditional advice has been to use different passwords for different applications. This is plainly impossible. A typical user of the Internet probably has passwords for their MSN, Gmail, YahooMail, Flickr, Picassa, Facebook, MySpace, Bebo accounts, as well as for their bank, mobile phone company, energy company, and innumerable other sites, some of which they've probably forgotten that they signed up for.

So, instead of saying each account should have a different password, I'd suggest that the best thing to do is to have a few passwords, but to have some rules around the ones that you use regularly.

  1. Always pick a good password. There's a guide here that offers some ideas.
  2. Don't use the same password for a mail account that you used to set up a social networking account with. For example, if you use the same password for Hotmail as you do Facebook, and one or the other gets "broken in to", it's likely the other will, too. And then it's incredibly difficult to regain control of either.
  3. Do change them occasionally.
  4. Consider what you're protecting. Don't use the same password for all your important accounts (e.g. bank, email) and use a separate password for account for sites you're not overly bothered about (e.g. that Fraggle Rock appreciation site you signed up to)
  5. Don't share them! I know this sounds obvious but don't let anyone else have your password – think about what you're giving the access to. This is especially true for passwords at university or in the workplace – the risk is much greater than simply to your data as it could impact the whole organisation.

These aren't simply theoretical risks. In the last few months, I have dealt with situations including the hijacking of a Facebook and related Hotmail account – believe me when I say that this is not easy to resolve – and several instances where people have sent their usernames and passwords to scammers.

The reason scammers want your username and password in a place like a university is because they want to send spam through the universities mail system. Unfortunately, this can lead to the whole university being blacklisted as a spammer and no-one will be able to send or receive email.

Please take care of your passwords.

Wednesday, 7 October 2009

Webmail Passwords

It was bound to happen. Large lists of account details have been leaked that were compromised through phishing, where the owners of the accounts replied to emails requesting their passwords and, in some cases, the login details to alternative accounts. We put out a message at LSE fairly frequently that people should never hand out their usernames and passwords to anyone – hopefully a fairly unambiguous statement. And yet, we still get people doing it.

I have tried to do a little research into why people continually reply to these messages, and the answer I usually get is that the email making the request "looked official".

If you have any ideas on how to get the message across, I'd be very interested.

Monday, 5 January 2009

Trouble with unsolicited email

Many organisations have policies that state that it is unacceptable to send emails to large numbers of users either inside or outside the organisations if you don't have the recipients' consent. Mass emails present their own problems, especially with attachments. Here's a quick run down as to why.

Spam

The general term for mass unsolicited emails is "spam". The sorts of emails typically associated with spam are those for dodgy investments ("pump and dump" schemes), growth pills, religious messages, phishing attempts, viruses and everything in between. Many organisations have invested in anti-spam filtering technologies to reduce the amount of junk that they receive (see my previous posting relating to scam/phishing emails for some statistics). The technologies to identify spam is always a "best guess", using a variety of techniques, which means that some spam gets through and some legitimate emails get blocked.

At a very basic level, there are two main methods for preventing spam. Firstly, there are blacklists where servers who are known to send spam are prevented from sending any emails whatsoever to the organisation protected by anti-spam filtering. Secondly, emails that are received from "clean" servers have their content assessed to see if it matches the profile of known spam. If the score from this assessment is higher than the threshold decided upon by the protected organisation, it won't get through and, in many cases, the sender's servers are automatically added to the blacklist (or "greylist"). Rules vary for different products, but may include:

  • Sending to a large number of people
  • BCC'ing instead of sending to explicit addresses
  • Not including a standard greeting ("Dear Sue," for example)
  • Having a reply-to set differently to the sender's address

Organisation impact

A key point is that black-and greylists are shared and so if an organisation gets blacklisted it won't be able to communicate with any organisation using that black- or greylist. Members of an organisation can, quite unwittingly, get their organisation blacklisted, thereby causing a lot of inconvenience to their colleagues.

Which is why organisations take it seriously.

Data Protection

All of the discussion above is quite apart from whether the email addresses should have been collected in the first place and then used for the purpose of sending emails. If in doubt, talk to your data protection manager.

Disk Space

I also have to put a short note in here about disk space. While most modern email systems will store a single copy of an email destined for multiple recipients on an email server, as soon as the email is copied off, forwarded or archived, a copy is made and the amount of space it takes up doubles. So, mass emails that have 1MB attachments can take up significant amounts of space if sent to a large number of people. And disk space is not free.

LSE resources

If you're at the LSE and do want to send emails to large numbers of people, please see the LSE's policy on internal email communications and the Conditions of Use for IT Facilities.

Monday, 8 December 2008

The Twelve Scams of Christmas

I know I'm a bit late getting to this topic (Philip Virgo got there first) but I think it's worth blogging about this, too. Here is the only (?) Christmas carol to be adapted for information security:

The Twelve Scams of Christmas

Twelve Phishers phishing
Eleven Spammers spamming
Ten Bots a' herding
Nine Virus writers coding
Eight Snoopers snooping
Seven Worms a' spreading
Six Crackers cracking
Five Tro-jan Horses
Four Logic bombs
Three Software patches
Two Denials of Service
And a hacker at your back door!

Credits go to Philip Virgo, Margaret Smith (plus the other ISAF members) and the countless members of IT Services at LSE who had to endure this being actually sung to the music of "Twelve Days of Christmas".

The links go to GetSafeOnline. For more information, see the links on the right. I'll blog on each topic over the next few days.

Friday, 5 December 2008

The Anatomy of a Phishing Scam

We've been suffering from a plethora of phishing scams over the last few weeks at LSE. To put this into context, Messagelabs stop in excess of 250,000 spam e-mails from arriving at our mailboxes every week, which represents 25% of the total (1,108,000). So, when one does get through, it is a bit unusual. In the main, these don't cause a lot of disruption as most people are conditioned to ignore them. However, there's always someone who does reply and the IT department spends quite a bit of time clearing up the aftermath.

So, here is my one top tip to not getting caught:

Never, ever send your password to anyone by e-mail.

It's quite simple. No-one should ever ask you to disclose your password by e-mail and you should never, under any circumstances, give it to anyone.

What happens if you do

Here at LSE, we have a set of Conditions of Use for IT Facilities which clearly state that you shouldn't do this. Most organisations with an information security policy say the same thing. Generally, you can expect your account to be suspended as a minimum.

However, that's not all. Scammers will use the details that they have gained to abuse the account they have access to steal information and, most likely, send spam out from the account. This means that the account gets blacklisted. Which is a pain.

Phishing for Bank Details

This is obviously a subset of a much wider attempt to con people into handing out personal detail, either directly or trying to convince them that they are on a legitimate site. Many people have received e-mails, purportedly from their bank, asking them to log in by clicking a link in the e-mail and filling in all of their authentication information.

There is a simple way to avoid being duped by one of these e-mails. Never click on the links in the e-mail: always go directly to your bank by manually typing their website address in the address box of your browser.

Browser defences

On top of this, many web browsers now (or will soon) incorporate anti-phishing tools. For example, Mozilla Firefox has a feature that, if turned on, automatically blocks access to known phishing site.

If in doubt, don't click. And another tip: don't reply to these scam e-mails with some sarcastic comment: it only confirms your address and you'll end up getting more spam.