Dragan on Security

New poll is active on this blog now. Question is: “How many security incidents you have experienced in last 12 months?”.

Available answers are:

• 0
• 1 - 5
• 6 - 10
• more then 10

Thank you for voting.

Google released Ratproxy - passive web application security assessment tool. It is released under terms and conditions of the Apache License, version 2.0.

Here is Google’s description of tool:

Ratproxy is a semi-automated, largely passive web application security audit tool. It is meant to complement active crawlers and manual proxies more commonly used for this task, and is optimized specifically for an accurate and sensitive detection, and automatic annotation, of potential problems and security-relevant design patterns based on the observation of existing, user-initiated traffic in complex web 2.0 environments.

It seems that bad days came for MD5 and those who based hashes on it. It is possible to create two executable programs with different functionalities with identical MD5 hash. Therefore, it is possible to create malicious executable which has same MD5 hash as regular program. This can be done just by using public Internet information and tools.

Here is short story and list of resources that you can be interested in to try.

In March 2005, Xiaoyun Wang and Hongbo Yu of Shandong University in China published paper “How to Break MD5 and Other Hash Functions” in which they described an algorithm that can find two different sequences of 128 bytes with the same MD5 hash. That article originally was here, but it seems as it not anymore. You can buy it from SpringerLink (here) for price of $25, or download based on subscription to it. There is free Power Point presentation here.

Abstract of paper “How to Break MD5 and Other Hash Functions” says:

MD5 is one of the most widely used cryptographic hash functions nowadays. It was designed in 1992 as an improvement of MD4, and its security was widely studied since then by several authors. The best known result so far was a semi free-start collision, in which the initial value of the hash function is replaced by a non-standard value, which is the result of the attack. In this paper we present a new powerful attack on MD5 which allows us to find collisions efficiently. We used this attack to find collisions of MD5 in about 15 minutes up to an hour computation time. The attack is a differential attack, which unlike most differential attacks, does not use the exclusive-or as a measure of difference, but instead uses modular integer subtraction as the measure. We call this kind of differential a modular differential. An application of this attack to MD4 can find a collision in less than a fraction of a second. This attack is also applicable to other hash functions, such as RIPEMD and HAVAL.

In meantime, Peter Selinger from Department of Mathematics and Statistics, Dalhousie University, published the tool that you can download for free and which he used to create MD5-colliding executable files. He calls it the “evilize” library. This software is based on Patrick Stach’s implementation of Wang and Yu’s algorithm. You can find his original implementation here.

Eduardo Diaz has described a scheme by which two programs could be packed into two archives with identical MD5 hash. A special “extractor” program turns one archive into a “good” program and the other into an “evil” one.

Almost three years ago I had published blog post on MD5 Online Cracking. Also, I have written about NIST new hash competition here and here.

[Thanks to Zeljko for pointing me to this implementation of tool.]

I had already written the post about NIST Competition for New Cryptographic Hash Function on my blog. Here are updates based on article by William E. Burr, “A New Hash Competition”, IEEE Security and Privacy, vol. 6,  no. 3,  pp. 60-62,  May/Jun,  2008.

Author says in abstract:

Since the discovery of collision attacks against several well-known cryptographic hash functions in 2004, a rush of new cryptanalytic results cast doubt on the current hash function standards. The relatively new NIST SHA-2 standards aren’t yet immediately threatened, but their long-term viability is now in question. The US National Institute of Standards and Technology (NIST) has therefore begun an international competition to select a new SHA-3 standard. This article outlines the competition, its rules, the requirements for the hash function candidates, and the process that NIST will use to select the final winning SHA-3 standard.

And then, in article:

NIST expects to launch a Hash Competition Conference to review the initial submissions in February 2009; the second conference will occur roughly a year later in 2010 to review public comments submitted on the submissions and their analysis. Following this second conference, NIST will select a small number of finalist candidates (probably five or so) for intensive review by the community. If, as we expect, we get 20 or more initial submissions, we’ll inevitably hear some disagreements about the finalists, but we can only intensively analyze a small number of algorithms, and, as in the AES competition, all the finalists will be good hash functions, although we might have to drop some worthy submissions.

Cryptanalysis of the finalists will be the tricky part—the time that skilled cryptanalysts can donate is the limiting resource here.

NIST is building up its limited cryptanalytic resources, but will rely heavily on the global cryptographic research community to do the bulk of the cryptanalysis. If the AES competition is any model, many analysis papers on the candidates will be submitted to various conferences. NIST will tentatively review the cryptanalysis results and review performance in a third workshop scheduled for 2012, after which they will select a winner.

The winning team might get nothing but glory for their huge effort. NIST expects the best people in the world to participate, as they did in the AES competition, because the community believes an open competition is the best way to select cryptographic standards. NIST expects to work hard, have fun, and significantly advance the state of the art while giving the world a valuable, secure hash function standard.

We Are Sorry to Inform You - about rejected papers of famous researchers.

Also interesting: “Once upon a time there was a little-known patent clerk in Bern who received a disappointing annual performance review in ‘05 - Annual Performance Review: Albert Einstein“.

You’ll probably be surprised when you see this.

I was on holidays when new release of WordPress 2.5.1 came out. And I wanted to upgrade immediately from 2.5.0. to new version. But I haven’t got computer with me and had just mobile phone (Nokia N95) with its browser. Anyhow, I decided to try automatic upgrade from mobile. I took the huge risk (I thought). And… it worked fine. Everything was easy and went smoothly with upgrade.

Congratulations to WordPress team. That is really exceptional.

Do you owe cell phone? Yes, of course. Then read this: Cell Phone Spying: Is Your Life Being Monitored?

It says:

It connects you to the world, but your cell phone could also be giving anyone from your boss to your wife a window into your every move.  The same technology that lets you stay in touch on-the-go can now let others tap into your private world — without you ever even suspecting something is awry.

and

You don’t have to plant a CIA-style bug to conduct surveillance any more.  A service called World Tracker lets you use data from cell phone towers and GPS systems to pinpoint anyone’s exact whereabouts, any time — as long as they’ve got their phone on them.

Also:

Dozens of programs are available that’ll turn any cell phone into a high-tech, long-range listening device.  And the scariest part?  They run virtually undetectable to the average eye.

Take, for example, Flexispy.  The service promises to let you “catch cheating wives or cheating husbands” and even “bug meeting rooms.”  Its tools use a phone’s microphone to let you hear essentially any conversations within earshot.  Once the program is installed, all you have to do is dial a number to tap into the phone’s mic and hear everything going on.  The phone won’t even ring, and its owner will have no idea you are virtually there at his side.

Is that legal?

You won’t find it on the flashy front page, but buried a bit further in the site, the company says you’re fine to use their program only “on a phone that you own, for protecting your children,” or for purposes like “archiving data.”  It’s a bit of a contrast from the bold suggestions of “uncover[ing] employee espionage,” “catch[ing] cheating husbands,” and “bug[ging] meeting rooms” that fill the company’s materials.  After a little more explanation, their answer as to the legality of the service ends with a broad statement: “Please consult a qualified lawyer in your country for the correct answer to this question.”

Let me make it easier for you: Once you get into listening in to private conversations without either party’s consent, you’re treading rough water that could sweep you straight into jail.  Whether it’s an employee or a spouse on the receiving end of your mission, neither federal nor state privacy laws take violations lightly in America.  Getting caught could cost you several years behind bars, among other serious penalties.

And can it be detected?

Finding spyware on your phone isn’t easy.  There are dozens of bug detectors available from surveillance companies, but the only true fix is taking your phone to your provider and having them wipe it out altogether.  That will restore the factory settings and clear out any hidden software that’s running on your phone.

Scary, isn’t it? I would strongly suggest to keep your hands far from this.

But also I would suggest to use security software for your cell. For example, there is F-Secure Mobile and I have been using it for some time. Two products can be very helpfull F-Secure Mobile Anti-Virus(TM) and F-Secure Mobile Security(TM). Here are some details:

F-Secure Mobile Anti-Virus(TM)

• F-Secure Mobile Anti-Virus(TM) is easy to use and does not require excess device resources or unnecessary user interaction.
• It automatically scans all files in the background, both in the device and on the memory cards.
• When an infected file is detected it is immediately quarantined to protect all other data in the system.
• The antivirus database is updated invisibly in the background when a data connection is used for emails, web browsing etc.

F-Secure Mobile Security(TM)

• F-Secure Mobile Security enables secure mobile computing by combining an integrated antivirus and firewall.
• Device-recident protection safeguards the mobile device from any type of attack, from intrusion attempts to malware.
• The solution delivers invisible and automated safety through real-time, on-device protection with easy to use firewall rule sets and automatic over-the-air antivirus updates
• F-Secure Mobile Security scans both incoming and outgoing internet/network data packets. It stops malicious, unwanted, harmful, or possibly dangerous packets.
• F-Secure Mobile Security is designed to be easy to use and delivers protection without need for unnecessary user intervention.

We can expect much more to come soon.

Poll “Primary motives for hacking are” which was open on this blog since December 21, 2007 to March 31, 2008 is closed now. Based on answers of visitors, who took opportunity to vote in the poll, main reason why hackers (malicious ones) are attacking is because they take it as intellectual challenge. Next reason is money etc.

Here is summary of results.

As it was said in introductory post for poll, it is based on Australian government Institute of Criminology i.e. its High tech crime centre classification. You can see paper (linked in blog post also) here.

There were polemic about definition of hackers and is that correct to say that hackers are malicious. Many people think that definition of hackers mean that they “wear white hat” i.e. hackers are not driven by malicious motives. However, crackers are ones who “wear black hat” i.e. they are supposed to be malicious, according that opinion. Also, some people mentioned that poll lacks precise definition of hacking and description of hacker and cracker difference for sake of this poll.

This poll is about public opinion - what people think about hackers and their motives, so it was left to opinions and thoughts of everyone and a little bit imprecise (intentionally). :)

You can look into Merriam-Webster’s dictionary definition of hacker – it may be interesting.

If you’ve thought your data are secure on encrypted hard disk, read: Lest We Remember: Cold Boot Attacks on Encryption Keys. Researchers with Princeton University and the Electronic Frontier Foundation (EFF) have found a flaw that renders disk encryption systems useless if an intruder has physical access to your computer - say in the case of a stolen laptop or when a computer is left unattended on a desktop in sleep mode or while displaying a password prompt screen. The attack takes only a few minutes to conduct and uses the disk encryption key that’s stored in the computer’s RAM.

There is also full research paper and YouTube video about this attack.

Abstract says:

Contrary to popular assumption, DRAMs used in most modern computers retain their contents for seconds to minutes after power is lost, even at operating temperatures and even if removed from a motherboard. Although DRAMs become less reliable when they are not refreshed, they are not immediately erased, and their contents persist sufficiently for malicious (or forensic) acquisition of usable full-system memory images. We show that this phenomenon limits the ability of an operating system to protect cryptographic key material from an attacker with physical access. We use cold reboots to mount attacks on popular disk encryption systems — BitLocker, FileVault, dm-crypt, and TrueCrypt — using no special devices or materials. We experimentally characterize the extent and predictability of memory remanence and report that remanence times can be increased dramatically with simple techniques. We offer new algorithms for finding cryptographic keys in memory images and for correcting errors caused by bit decay. Though we discuss several strategies for partially mitigating these risks, we know of no simple remedy that would eliminate them.

[Thanks to colleague Sanida O. for bringing this to my attention].

I’ve added a new poll to this blog. The aim of the poll is to see what is the structure of the blog visitors according their (your) individual opinion and experience in the field of security knowledge. There is no guidance and explanation of the given choices. You are the one who sets measurement units, decides and rates your own knowledge and experience according to it.

Question is: “Rate your computer security knowledge and experience”, and possible answers are:

• None
• Beginner
• Moderate
• Expert
• Guru

Vote and enjoy visiting often and seeing how others vote. Polls started today and it is planned to be open 3 months i.e. by end of June 2008.

An earlier poll “Hacking Motives” expired last night (March 31, 2008). I am going to discuss results in future post on this blog.