Monday, September 23, 2013

Quantum Computer

A quantum computer is any device for computation that makes direct use of distinctively quantum mechanical phenomena, such as superposition and entanglement, to perform operations on data.

In a classical computer, information is stored as bits; in a quantum computer, it is stored as qubits. The basic principle of quantum computation is that the quantum properties can be used to represent and structure data and that quantum mechanisms can be devised and built to perform operations with this data. Although quantum computing is still in its infancy, experiments have been carried out in which quantum computational operations were executed on a very small number of qubits.

Research in both theoretical and practical areas continues at a frantic pace, and many national government and military funding agencies support quantum computing research to develop quantum computers for both civilian and national security purposes, such as cryptanalysis. If large-scale quantum computers can be built, they will be able to solve certain problems exponentially faster than any of our current classical computers.

Quantum computers are different from other computers such as DNA computers and traditional computers based on transistors. Some computing architectures such as optical computers may use classical superposition of electromagnetic waves, but without some specifically quantum mechanical resources such as entanglement, they have less potential for computational speed-up than quantum computers. The power of quantum computers Integer factorization is believed to be computationally unfeasible with an ordinary computer for large integers that are the product of only a few prime numbers.

By comparison, a quantum computer could solve this problem more efficiently than a classical computer using Shor's algorithm to find its factors. his ability would allow a quantum computer to "break" many of the cryptographic systems in use today, in the sense that there would be a polynomial time (in the number of bits of the integer) algorithm for solving the problem. In particular, most of the popular public key ciphers are based on the difficulty of factoring integers, including forms of RSA.

These are used to protect secure Web pages, encrypted email, and many other types of data. Breaking these would have significant ramifications for electronic privacy and security. The only way to increase the security of an algorithm like RSA would be to increase the key size and hope that an adversary does not have the resources to build and use a powerful enough quantum computer. It seems plausible that it will always be possible to build classical computers that have more bits than the number of qubits in the largest quantum computer.

Saturday, September 21, 2013

Malware and Ransomware

Kits lead to an explosion in malware for OS X and mobile
Given the popularity of mobile computing, we should perhaps be surprised that cybercriminals have taken so long to extensively exploit this field. In 2012, however, we’ve seen the number of mobile threats go up dramatically. As we look at them in more detail, we see the large amount of Windows based malware owes its existence to the easy availability of malware kits in the underground market. In 2013, there is a good chance ransomware kits will take the lead from malware kits. Now the first ransomware kits are being marketed in the underground.

Ransomware continues to expand to mobile devices
Ransomware on Windows PCs has more than tripled during the past year. Attackers have proven that this “Business Model” works and are scaling up their attacks to increase profits. One way ransomware is different from other types of malware such as backdoors, keyloggers and password stealers is that attackers do not rely on their victims using the infected systems for financial transactions to separate them from their money. Instead these criminals hijack the users ability to access data, communicate or use the system at all. The victims are faced with either losing their data or paying a ransom in the hope of regaining access.

One limitation for many malware authors seeking profit from mobile devices is that more users transact business on desktop PCs rather than on tablets or phones. But this trend may not last; the convenience of portable browsers will likely lead more people do their business on the go. Attackers have already developed ransomware for mobile devices.

Botnets and Spam


The biggest threat to botmasters is the unrecoverable loss of their botnets. International cooperation in policing spam, malware, child exploitation, and illegal pills has made that loss a reality for many major botnets over the past few years, and will continue to threaten the proliferation of botnets. When the largest botnets get taken down, then the next largest botnets become the new targets. Botmasters have already reacted to this activity by subdividing botnets and increasing the costs associated with activities that are easily detectable (such as DDoS and spam). It is only a matter of time before botmasters implement fail-safes to reestablish command of a botnet that has lost all of the control servers it usually reports to.

In many cases botnets are temporarily hijacked by whitehat security researchers. Due to possible negative side effects, however, these takeovers do not lead to new commands reaching the infected hosts. There is a massive liability issue associated with the unauthorized remote operation of systems, even with the best of intentions. Pushing new commands to an old Windows machine serving a hospital could turn the PC into a brick and lead to incorrect care or even the death of a patient. Botmasters will take advantage of this reluctance by the good guys to meddle by hard wiring their botnets to reestablish control after a take down.

“Snowshoe” spam will continue to increase
When a shady marketing company approaches your marketing people and tells them that they have a list of email addresses that have already opted into receiving whatever advertising you want to send them, it should set off alarm bells. Unfortunately those bells don’t ring often enough. Well known companies selling products from cell phones to cigars to language-learning software to satellite TV to medical supplies have all signed on with these shady advertisers. The shady companies blast out millions and millions of blatantly illegal spam messages every day from newly rented hosts in hosting companies until they get evicted from their subnets or move on after they have turned those addresses, and sometimes the subnets, into permanently blacklisted wastelands. Recipients have their in boxes bombarded with these spam messages and are unable to opt out of them.

Because this sort of activity is not as malicious as the most newsworthy hacks and malware, this area has been mostly ignored by the authorities. Nonetheless, this practice of snowshoe spamming has exploded during the past two years and is currently one of the biggest problems in the spam world. Attempts by researchers to expose this sort of activity have resulted in threats of defamation lawsuits by the companies using these shady marketers. In that environment, this sort of activity will only continue to increase at the breakneck pace that we have seen.

SMS spam from infected phones
Cell phone providers are working to prevent SMS spam. Their primary method of receiving reports from consumers is for the latter to forward messages to SPAM (7726) on their phones and report the messages so that they can be blocked. An infected phone can also send spam text messages; then the victims face the problem of having their accounts closed by the providers.