It seems that many users are receiving Phishing phone calls through Skype from a profile called 'ONLINE HELP'. This call, if answered, plays a recorded message telling the user that their computer is not protected and that they must go to visit www.hosog.com. If you do visit this site, it is riddled with malware. This is a phishing scam!
The user account that I have observed is drationlinehelpgb and shows as being registered in the US, but seems to have been taken down now. However, others have reported a user account of drajizonlinehelp, which appears to be registered in Afghanistan. This one is still live at the time of writing and is using the same 'ONLINE HELP' profile name. It would appear that new accounts are being created as the old ones are blocked by people and reported for abuse to Skype.
It is slightly worrying the number of people who are reporting having answered this call. If you receive any unsolicited calls through Skype from users outside your contacts, don't answer them. Indeed you should actually change your privacy settings in Skype if you haven't already. Choose the Privacy... menu item in the Skype menu to open up the Privacy settings tab in the Options dialog. Make sure that all the options are set to people in my Contact list only. I suggest that you also don't share your online status on the Web. You shouldn't now receive calls out of the blue from scammers.
The problem is that people are becoming trained into accepting connections in social media sites and it spills out into their other online activities. People still think that SPAM and phishing scams only happen over email. Actually, people are usually fairly vigilant with their email, so it is more likely to be successful if they try other avenues. Sophos did an experiment at the end of 2009 where they created two fictitious Facebook users, one with a profile picture of a rubber duck. They had thousands of people sign up to 'friend' them. How carefully do users check links from their 'friends'? It opens up a very good channel for SPAM and phishing attacks. As a general rule of thumb don't connect or share details with anyone you don't personally know through social media, voip, email, etc. Also, if you use these media channels a lot, you should think about investing in a security product to help protect you.
Thursday, 9 June 2011
Friday, 3 June 2011
Google email Accounts Compromise
I was asked to comment yesterday on the story that emerged about the Google mail accounts that were compromised over the last few days, so I thought I'd put some of my answers down here. First off, Google wasn't compromised; a set of phishing emails were sent out and a fake Gmail login set up to harvest login details. These were used to set up forwarding rules to copy mail to another account.
Unfortunately, although a large number of people are aware of phishing and are (to a certain extent) vigilant, it only takes one person within the organisation to fall for the attack to compromise security. The scammers are becoming better at targeting people and making the initial phishing contact more believable to some people. Phishing is not just about email, although that is the most common avenue for the initial contact. Social media is also commonly used and we have seen the use of SEO to force phishing sites to the top of search engine rankings as well. User education is the only real way out of this.
Could this be cyber espionage? I would think that is most likely given the profile of those targeted. Information is worth a lot of money and political weight. In recent years we have seen a decrease in attacks designed to deface/destroy/delay/deny services and information. Instead, we are now seeing information and identity theft as major goals. Viruses won't necessarily stop your computer from working, but they will use Trojans to steal your login credentials. Malware now will silently sign your machine up to botnets rather than perform an obviously malicious action.
What can companies like Google do to stop this? Well, they can improve their SPAM filtering for a start. It is possible to eliminate the vast majority of phishing emails, which would drastically reduce the problems. However, many of the major vendors aren't strong enough on this. Secondly, user education would help a lot, but can't always help you against the best social engineers. To be honest, though, the governments and organisations that these people work for shouldn't allow the use of gmail, or other accounts (which have fewer controls than a corporate email setup), for official business and should educate their users to use different passwords, be vigilant, etc.
Spear phishing is a more difficult one to combat as it targets a specific user or group of users that the attacker has knowledge of. If I know your habits and who your friends are then I can use that information to trick you much more easily. If you receive an email or Facebook message from your partner, do you hesitate before opening it? The reason this doesn't happen more is that it takes background research and, by definition, targets very few people. This technique is only relevant if you want what that specific user has access to. Hence it is more likely to be information that they were after.
Another way to combat these types of attack is to use one-time passwords as well, so that intercepting a single logon only gives you access during that session, and isn't valid in the future. However, tokens are prohibitively expensive for Google to hand out to everyone. There are other solutions such as SMS tokens, but these aren't all that cheap, when multiplied up by the number of gmail users, and aren't without their problems. Software token solutions such as Swivel, GrIDsure, FireID, etc., are possibly cost-effective enough to be implemented and could drastically reduce the success of these attacks. However, none of these stop the man-in-the-middle (MITM) attack, so you could still hijack the session and set up a forwarding rule to obtain a copy of all their mail. Google do allow you to set up alerts and have to validate changes through a 2-step process, but you have to enable this. This should be the default for all of these services. Perhaps they could also add a footer to all versions of the email to specify where it has been forwarded to.
How worrying is this sort of attack? Well, that depends. Most people can be socially engineered - look at Derren Brown! For the individual, spear phishing is unlikely to be a problem, but with a lack of education they may well fall for a bulk phishing scam anyway (thousands do or nobody would bother). However, for those with access to secrets or other valuable information, it is a serious issue. It all comes down to how good the attacker is. I believe that HM Treasury is the most attacked entity in this country and that is mostly for information rather than evading tax or performing Denial-of-Service, etc. They should be worried about this type of attack.
Unfortunately, although a large number of people are aware of phishing and are (to a certain extent) vigilant, it only takes one person within the organisation to fall for the attack to compromise security. The scammers are becoming better at targeting people and making the initial phishing contact more believable to some people. Phishing is not just about email, although that is the most common avenue for the initial contact. Social media is also commonly used and we have seen the use of SEO to force phishing sites to the top of search engine rankings as well. User education is the only real way out of this.
Could this be cyber espionage? I would think that is most likely given the profile of those targeted. Information is worth a lot of money and political weight. In recent years we have seen a decrease in attacks designed to deface/destroy/delay/deny services and information. Instead, we are now seeing information and identity theft as major goals. Viruses won't necessarily stop your computer from working, but they will use Trojans to steal your login credentials. Malware now will silently sign your machine up to botnets rather than perform an obviously malicious action.
What can companies like Google do to stop this? Well, they can improve their SPAM filtering for a start. It is possible to eliminate the vast majority of phishing emails, which would drastically reduce the problems. However, many of the major vendors aren't strong enough on this. Secondly, user education would help a lot, but can't always help you against the best social engineers. To be honest, though, the governments and organisations that these people work for shouldn't allow the use of gmail, or other accounts (which have fewer controls than a corporate email setup), for official business and should educate their users to use different passwords, be vigilant, etc.
Spear phishing is a more difficult one to combat as it targets a specific user or group of users that the attacker has knowledge of. If I know your habits and who your friends are then I can use that information to trick you much more easily. If you receive an email or Facebook message from your partner, do you hesitate before opening it? The reason this doesn't happen more is that it takes background research and, by definition, targets very few people. This technique is only relevant if you want what that specific user has access to. Hence it is more likely to be information that they were after.
Another way to combat these types of attack is to use one-time passwords as well, so that intercepting a single logon only gives you access during that session, and isn't valid in the future. However, tokens are prohibitively expensive for Google to hand out to everyone. There are other solutions such as SMS tokens, but these aren't all that cheap, when multiplied up by the number of gmail users, and aren't without their problems. Software token solutions such as Swivel, GrIDsure, FireID, etc., are possibly cost-effective enough to be implemented and could drastically reduce the success of these attacks. However, none of these stop the man-in-the-middle (MITM) attack, so you could still hijack the session and set up a forwarding rule to obtain a copy of all their mail. Google do allow you to set up alerts and have to validate changes through a 2-step process, but you have to enable this. This should be the default for all of these services. Perhaps they could also add a footer to all versions of the email to specify where it has been forwarded to.
How worrying is this sort of attack? Well, that depends. Most people can be socially engineered - look at Derren Brown! For the individual, spear phishing is unlikely to be a problem, but with a lack of education they may well fall for a bulk phishing scam anyway (thousands do or nobody would bother). However, for those with access to secrets or other valuable information, it is a serious issue. It all comes down to how good the attacker is. I believe that HM Treasury is the most attacked entity in this country and that is mostly for information rather than evading tax or performing Denial-of-Service, etc. They should be worried about this type of attack.
Saturday, 30 April 2011
3M Privacy Filters Update
I have blogged about 3M's privacy filters before and their gold filter still remains, in my opinion, the best privacy filter on the market. If you want to find out more about that one and why you need a privacy filter, see my previous blog post "Why do I need a privacy filter? (3M's new Vikuiti Gold Privacy Filter)". I also blogged about their mobile phone privacy filter.
The problem with their mobile phone privacy filter last year was that it was only available in their standard grey louvered filter, so didn't work well with accelerometer phones that can be used in portrait or landscape modes - you had to pre-select which orientation you wanted to use your smartphone in. Also, the light transmission wasn't as good as the gold filter nor was the touch quite as good after applying it.
The problem with their mobile phone privacy filter last year was that it was only available in their standard grey louvered filter, so didn't work well with accelerometer phones that can be used in portrait or landscape modes - you had to pre-select which orientation you wanted to use your smartphone in. Also, the light transmission wasn't as good as the gold filter nor was the touch quite as good after applying it.
Well, they've addressed this and lanuched a new filter for mobile phones and slates at InfoSecurity Europe. The filter is now significantly thinner with excellent touch response and better light transmission - they also have a clarity measure which makes the screen easier to read with the filter (it does kind of work, having seen an iPad with only half the screen covered). They also have (in the lab) a grey louvered filter in two planes. This stops people from being able to read the screen if they aren't directly in front of it and deals with mobile phones and slate devices that can be used in the two orientations. This filter isn't available yet, but 3M told me that they were targeting the end of this year for these new filters. 3M also assured me that the new filter with double-louvers will be no thicker than the current one. This, combined with 3M's great adhesive that allows for a simple application, will make 3M's new privacy filters for mobile phones and slates the one to have, especially as they double as screen protectors.
Unfortunately they only do pre-cut versions for iPhones, iPads and HTC phones at the moment. If you don't have one of these then you will have to either cut it yourself or get a third party to cut one for you.
Friday, 29 April 2011
InfoSecurity Europe 2011
InfoSecurity Europe is over for another year. Once again there were several interesting companies and sessions worth noting. The 'themes' (if they can be called that) or 'hot topics' were cloud security again, social media and mobile access/the consumerisation of IT. The big difference seemed to be in the attitudes of people - more 'how can we reduce the risks to an acceptable level?' rather than 'we can't secure it, so we won't allow it!'
We are seeing a shift in the types of systems end users are accessing the corporate network from. The IT department are no longer dictating what will or will not be allowed. More and more users want to use their own personal devices, such as iPhones or iPads, on the network. In the past IT departments have resisted this and said no to the users. However, this attitude is beginning to change and there were a raft of organisations with solutions to help secure these devices and manage the data they contain. However, an awareness of risk and what it means to consumer devices and ownership must be understood beforehand.
With cloud security a big issue, and still stopping some organisations from adopting cloud services, I decided to speak to some of the cloud services providers about their security. Many of them couldn't give me the real technical details, but some of them did have some reassuring things to say. Unfortunately, not all services are equal and organisations are still going to have to do a lot of research on the providers and make sure that they ask to see independant reports on the security of any potential provider. Make sure you ask them the difficult technical questions and only use their service if you are happy with their answers. Again, always remember that you can't outsource risk, so think carefully about what you want to use the cloud for.
Social media is still an issue that some organisations are solving by blocking it and others are ignoring. With the latest generation of products, again we can be quite granular with the level of access granted to social media, so a default blocking isn't necessary in all circumstances. The (ISC)2 have conducted a very interesting survey on security that shows some interesting trends, not least of which is that 49% of organisations block Facebook and around 20% don't monitor social networks at all. As social engineering and backdoors through user activity are some of the main causes of problems, this is worrying. Indeed, the survey showed that security professionals put education and policy mechanisms as the top 6 security security solutions required, with software and technologies coming in 7th and 8th respectively.
We are seeing a shift in the types of systems end users are accessing the corporate network from. The IT department are no longer dictating what will or will not be allowed. More and more users want to use their own personal devices, such as iPhones or iPads, on the network. In the past IT departments have resisted this and said no to the users. However, this attitude is beginning to change and there were a raft of organisations with solutions to help secure these devices and manage the data they contain. However, an awareness of risk and what it means to consumer devices and ownership must be understood beforehand.
With cloud security a big issue, and still stopping some organisations from adopting cloud services, I decided to speak to some of the cloud services providers about their security. Many of them couldn't give me the real technical details, but some of them did have some reassuring things to say. Unfortunately, not all services are equal and organisations are still going to have to do a lot of research on the providers and make sure that they ask to see independant reports on the security of any potential provider. Make sure you ask them the difficult technical questions and only use their service if you are happy with their answers. Again, always remember that you can't outsource risk, so think carefully about what you want to use the cloud for.
Social media is still an issue that some organisations are solving by blocking it and others are ignoring. With the latest generation of products, again we can be quite granular with the level of access granted to social media, so a default blocking isn't necessary in all circumstances. The (ISC)2 have conducted a very interesting survey on security that shows some interesting trends, not least of which is that 49% of organisations block Facebook and around 20% don't monitor social networks at all. As social engineering and backdoors through user activity are some of the main causes of problems, this is worrying. Indeed, the survey showed that security professionals put education and policy mechanisms as the top 6 security security solutions required, with software and technologies coming in 7th and 8th respectively.
Wednesday, 9 March 2011
Base64 Encoding is NOT Cryptography
I have once again come across an IT department who were/are firmly convinced that the commercial web application that they use is secure and has encrypted user details. What it actually does is Base64 encode the password. This is not encryption and must be treated as plaintext.
So what is Base64 encoding and why do we have it? Well, a large number of popular application layer protocols are ASCII text based, i.e. they transfer plain text over the network. A good example of this is HTTP - the protocol used to transfer HTML (or Web) pages around. Originally, only text pages were sent with markup embedded to style it. However, soon other resources were added to the web including pictures, documents, etc. HTTP is designed to transfer plain ASCII text, so how do you transfer a JPEG photograph? Answer: You convert it into plain ASCII text.
The basic principle of converting a file into text is to use the data to represent an index to the ASCII character, e.g. 'A' is 63, 'B' is 64, 'a' is 97, '8' is 56, etc. So, if the first four bytes of your file are 63, 64, 97 and 56, this can be represented by 'ABa8' without loss. However, ASCII is actually only 7 bits and we usually use 8-bit bytes (because of IBM setting the standard - actually a byte was historically just the number of bits required to store a character). Also, ASCII character 13 is a carriage return, 27 is escape and 8 is backspace. These are non-printable and, worse than that, could corrupt the communications as well as remove other characters. So, we can't just do a straight conversion from bytes to ASCII.
This is where Base64 conversion comes in. We split the file up into 6-bit 'bytes', rather than 8-bit. 6 bits give us 64 possible values. These are then represented by the digits, upper and lowercase letters and a couple of symbols ensuring that they are always printable and don't cause problems. So, the Base64 encoded password is just a 6-bit 'byte' representation of an 8-bit byte password and it is trivial to convert between the two. There is no security in Base64 encoding anything. Perhaps I should repeat that again.
Base64 encoding something is not encrypting it and provides NO SECURITY whatsoever!
I am constantly surprised and disappointed that people think that Base64 encoding something will protect it. I know TLS has its problems, but why aren't all web applications using it?
The little JavaScript tool below will allow you to encode and decode Base64 encoded text to see what it's like and how simple it is. If you find Base64 encoded passwords on your network via sniffing then you can use this to decode them.
Enter Text:
Select Encoding or Decoding:
So what is Base64 encoding and why do we have it? Well, a large number of popular application layer protocols are ASCII text based, i.e. they transfer plain text over the network. A good example of this is HTTP - the protocol used to transfer HTML (or Web) pages around. Originally, only text pages were sent with markup embedded to style it. However, soon other resources were added to the web including pictures, documents, etc. HTTP is designed to transfer plain ASCII text, so how do you transfer a JPEG photograph? Answer: You convert it into plain ASCII text.
The basic principle of converting a file into text is to use the data to represent an index to the ASCII character, e.g. 'A' is 63, 'B' is 64, 'a' is 97, '8' is 56, etc. So, if the first four bytes of your file are 63, 64, 97 and 56, this can be represented by 'ABa8' without loss. However, ASCII is actually only 7 bits and we usually use 8-bit bytes (because of IBM setting the standard - actually a byte was historically just the number of bits required to store a character). Also, ASCII character 13 is a carriage return, 27 is escape and 8 is backspace. These are non-printable and, worse than that, could corrupt the communications as well as remove other characters. So, we can't just do a straight conversion from bytes to ASCII.
This is where Base64 conversion comes in. We split the file up into 6-bit 'bytes', rather than 8-bit. 6 bits give us 64 possible values. These are then represented by the digits, upper and lowercase letters and a couple of symbols ensuring that they are always printable and don't cause problems. So, the Base64 encoded password is just a 6-bit 'byte' representation of an 8-bit byte password and it is trivial to convert between the two. There is no security in Base64 encoding anything. Perhaps I should repeat that again.
Base64 encoding something is not encrypting it and provides NO SECURITY whatsoever!
I am constantly surprised and disappointed that people think that Base64 encoding something will protect it. I know TLS has its problems, but why aren't all web applications using it?
The little JavaScript tool below will allow you to encode and decode Base64 encoded text to see what it's like and how simple it is. If you find Base64 encoded passwords on your network via sniffing then you can use this to decode them.
Enter Text:
Select Encoding or Decoding:
Thursday, 17 February 2011
Security Risk is Proportional to Hacker's Skill
There are many factors that influence the risk to your organisation and they are by no means all about hackers. However, we do have to deal with hackers and have to realise that they are a fact of life that won't ever go away. So how much risk are we at from hackers?
The truth of the matter is that the risk your organisation faces from hackers is proportional to the skill of the hacker. There are many different types of hacker, from the person who downloads a free tool, through script kiddies to highly intelligent, technically skilled people who can discover and exploit any vulnerabilities you may have.
The tricky thing is to figure out who you will likely get attacked by. Many organisations have the attitude that they are not a natural target so nobody will attack them and they don't need to worry about security. Unfortunately that just isn't true. Computers are very good at doing repetitive tasks without getting bored. As a test we have standard ADSL line with a web server sitting on it, which is completely non-advertised, yet it gets attacked 4 times a day on average. The problem is that if you have simple vulnerabilities or use the same components and services as others that are targets then they could be discovered on your network and exploited by simple to use tools. The problem is that the exploits are created and distributed in freely downloadable tools for all to use.
It is relatively easy for a hacker to find and exploit your system even if you aren't an obvious target.
The truth of the matter is that the risk your organisation faces from hackers is proportional to the skill of the hacker. There are many different types of hacker, from the person who downloads a free tool, through script kiddies to highly intelligent, technically skilled people who can discover and exploit any vulnerabilities you may have.
The tricky thing is to figure out who you will likely get attacked by. Many organisations have the attitude that they are not a natural target so nobody will attack them and they don't need to worry about security. Unfortunately that just isn't true. Computers are very good at doing repetitive tasks without getting bored. As a test we have standard ADSL line with a web server sitting on it, which is completely non-advertised, yet it gets attacked 4 times a day on average. The problem is that if you have simple vulnerabilities or use the same components and services as others that are targets then they could be discovered on your network and exploited by simple to use tools. The problem is that the exploits are created and distributed in freely downloadable tools for all to use.
It is relatively easy for a hacker to find and exploit your system even if you aren't an obvious target.
Tuesday, 28 December 2010
True Random Numbers from Random.org
Much of security relies on randomness - encryption keys should be random and random passwords are more secure than dictionary words or predictable sequences. The problem is, how do we generate a random number?
Well, actually, this is a trick question. The answer is that you can't generate random numbers, but you can observe them. Most programming languages give you a random number generator, so why not just use that? Well, it's not actually a random number generator, but a Pseudo-Random Number Generator (PRNG), or more accurately a Pseudo-Random Sequence Generator (PRSG). Given the same seed value, it will produce the same output every time. Try seeding the random number function in your favourite programming language then run your program a few times. You should see the same numbers coming out each time.
The reason for this is the function used to produce random numbers is just a mathematical formula that takes an input and gives an output. To have a random number out, you need a random starting value. Most will seed themselves on the clock, but this isn't random; it isn't even unpredictable. A simplistic example of a PRNG, as given by Knuth in his seminal books, is as follows:
X = (a*X+c) mod m
Random number = X/m for some suitable large prime number m and fixed values a and c both less than m (indeed c is usually a small number <10).
This can be seeded by setting X to the seed value and will give the same sequence of pseudo-random numbers out, as can be seen. However, it isn't random. If I know your seed value I can recreate your sequence of numbers. If you seed it on the clock it is often possible to work out a window of opportunity and obtain a range of seed values. Admittedly, this could be large, but an exhaustive search of these would be quicker than breaking the code that relies on them in many cases. Recently, a large Linux distribution was found to have a flaw in its key-generation that introduced a major weakness into the RSA public-key codes generated on those machines. This was due to predictability of the keys and a lack of randomness.
So, what can we do? We can observe randomness in the natural world. Random.org uses background white noise as a source of randomness. This gives good randomness and distribution of numbers. They offer several options to generate random numbers, sequences or even passwords. An example of their random number service is given below. I'm not saying that they are the best option or the only option, but you must use truly random numbers in your cryptography and secure systems.
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