Difference between pages "Past Selected Articles" and "File:1-BB9780-VendorPlateRemoval.jpg"

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''Archived past selected research articles''
[http://www.ojp.usdoj.gov/nij/journals/259/csi-effect.htm The 'CSI Effect': Does It Really Exist?], by The Honorable Donald E. Shelton
Crime and courtroom proceedings have long been fodder for film and television scriptwriters. In recent years, however, the media's use of the courtroom as a vehicle for drama has not only proliferated, it has changed focus. In apparent fascination with our criminal justice process, many of today's courtroom dramas are based on actual cases. Court TV offers live gavel-to-gavel coverage of trials over the Internet for $5.95 a month. Now, that's "reality television"!
Reality and fiction have begun to blur with crime magazine television shows such as 48 Hours Mystery, American Justice, and even, on occasion, Dateline NBC. These programs portray actual cases, but only after extensively editing the content and incorporating narration for dramatic effect. Presenting one 35-year-old cold case, for example, 48 Hours Mystery filmed for months to capture all pretrial hearings as well as the 2-week trial; the program, however, was ultimately edited to a 1-hour episode that suggested the crime remained a "mystery" . . . notwithstanding the jury's guilty verdict....
[http://hal.archives-ouvertes.fr/docs/00/35/09/62/PDF/ColDanDauDef09.pdf Using Graphics Processors for Parallelizing Hash-based Data Carving],  by Sylvain Collange, Marc Daumas, Yoginder S. Dandass, and David Defour, Proceedings of the 42nd Hawaii International Conference on System Sciences - 2009.
The ability to detect fragments of deleted image files and to reconstruct these image files from all available fragments on disk is a key activity in the field of digital forensics. Although reconstruction of image files from the file fragments on disk can be accomplished by simply comparing the content of sectors on disk with the content of known files, this brute-force approach can be time consuming.
This paper presents results from research into the use of Graphics Processing Units (GPUs) in detecting specific image file byte patterns in disk clusters. Unique identifying pattern for each disk sector is compared against patterns in known images. A pattern match indicates the potential presence of an image and flags the disk sector for further in-depth examination to confirm the match. The GPU-based implementation outperforms the software implementation by a significant margin.
;'''[http://blogs.sans.org/computer-forensics/2009/02/04/what-happens-when-you-overwrite-data/ What happens when you overwrite data?]'''.
Data recovery Craig S. Wright explores what happens when you try to cover overwritten data using high-quality scientific equipment. His conclusion: "The values do not tell you what existed on the drive prior to the wipe; they just allow you to make a guess, bit by bit. Each time you guess, you compound the error. As recovering a single bit value has little if any forensic value, you soon find that the cumulative errors render any recovered data worthless."
;'''[http://www.computer-forensics-lab.org/pdf/Linux_for_computer_forensic_investigators.pdf Linux for computer forensic investigators: «pitfalls» of mounting file systems] [http://computer-forensics-lab.org/lib/?cid=174 (Russian version)], Suhanov Maxim, 2009'''
The paper opens discussion about building forensically sound Live CD distributions based on Linux. Problems described:
* Common misconceptions about "-o ro" mount option (is it forensically sound?);
* Bugs in many forensic Live CDs that alter the data on evidentiary media.
Denis Frati ([[CAINE Live CD|CAINE]] developer) wrote an [http://www.denisfrati.it/pdf/Suhanov_Maxim_bug.pdf excellent review (Italian)] of the bug found in Casper scripts.
;'''[http://www.blackhat.com/presentations/bh-dc-08/FX/Whitepaper/bh-dc-08-fx-WP.pdf Cisco IOS Forensics]'''
"Cisco System’s routers running Cisco IOS are still the prevalent routing platform on the Internet and corporate networks. Their huge population, architectural deficiencies and hugely diverse version distribution make them a valuable target that gains importance as common operating system platforms are closed down and secured.
This paper takes the position that the currently used, well accepted practices for monitoring, debugging and post mortem crash analysis are insufficient to deal with the threat of compromised IOS devices. It sets forth a different method that reduces the requirement for constant logging, favoring on- demand in-depth analysis in case of suspicion or actual device crashes. The paper concludes by presenting the current state in the development of software supporting the proposed method and requesting feedback from the community on the software’s future directions."
;'''[http://viaforensics.com/wpinstall/wp-content/uploads/2009/08/Android-Forensics-Andrew-Hoog-viaForensics.pdf Android Forensics]'''
:Presentation on [http://viaforensics.com/android Android Forensics] by Andrew Hoog, Mobile Forensics World 2009. Presentation gives an overview of Android, explains how to root phones, and extract data from a phone once you have superuser access.  One of the complications is that Android phones (like the T-Mobile G1) use YAFFS2, a flash-specific file system.
; [http://ieeexplore.ieee.org/xpl/freeabs_all.jsp?tp=&arnumber=4505751&isnumber=4505671 Recovery of Damaged Compressed Files for Digital Forensic Purposes], Bora Park  Savoldi, A.  Gubian, P.  Jungheum Park  Seok Hee Lee  Sangjin Lee 
Korea Univ., Seoul,  International Conference on Multimedia and Ubiquitous Engineering, 2008. MUE 2008/
: Nowadays compressed files are very widespread and can be considered, without any doubt, with regard to the Digital Forensic realm, an important and precious source of probatory data. This is especially true when in a digital investigation the examiner has to deal with corrupted compressed files, which have been gathered in the collection phase of the investigative process. Therefore, in the computer forensic field, data recovery technologies are very important for acquiring useful pieces of data which can become, in a court of low, digital evidence. This kind of technology is used not only by law enforcement, but also by the multitude of users in their daily activities, which justify the relevant presence of tools in the software market which are devoted to rescue data from damaged compressed files. However, state-of-the-art data recovery tools have many limitations with regard to the capability of recovering the original data, especially in the case of damaged compressed files. So far, such recovery tools have been based on a which controls the signature/header of the file and, thus, provides the offset to the raw compressed data block. As a result, they cannot recover the compressed files if the first part of the raw compressed data block, which pertains to the header, is damaged or the signature/header block is corrupted. Therefore, in order to deal with this issue, we have developed a new tool capable of rescuing damaged compressed files, according to the DEFLATE compression scheme, even though the header block is missing or corrupted. This represents a new interesting opportunity for the digital forensic discipline.
; [[Media:JensenCellPhones.pdf|Overcoming Impediments to Cell Phone Forensics]], Wayne Jansen, Aurelien Delaitre, and Ludovic Moenner, Proceedings of the 41st Hawaii International Conference on System Sciences - 2008
:Cell phones are an emerging but rapidly growing area of computer forensics. While cell phones are becoming more like desktop computers functionally, their organization and operation are quite different in certain areas. For example, most cell phones do not contain a  hard drive and rely instead on flash memory for persistent storage. Cell phones are also designed more as special purpose appliances that perform a set of predefined tasks using proprietary embedded software, rather than general-purpose extensible systems that run common operating system software. Such differences make the application of classical computer forensic techniques difficult. Also complicating the situation is the state of the art of present day cell phone forensic tools themselves and the way in which tools are applied. This paper identifies factors that impede cell phone forensics and describes techniques to address two resulting problems in particular: the limited coverage of available phone models by forensic tools, and the inadequate means for validating the correct functioning of forensic tools
; [http://www.simson.net/clips/students/09_Farrell.pdf A Framework for Automated Digital Forensic Reporting], Lt. Paul Farrell, Master's Thesis, Naval Postgraduate School, Monterey, CA, March 2009
: Forensic analysis is the science of finding, examining and analyzing evidence in support of law enforcement, regulatory compliance or information gathering.  Today, almost all digital forensic analysis is done by humans, requiring dedicated training and consuming man-hours at a considerable rate.  As storage sizes increase and digital forensics gain importance in investigations, the backlog of media requiring human analysis has increased as well.  This thesis tests today's top-of-the-line commercial and open source forensic tools with the analysis of a purpose-built Windows XP computer system containing two users that engaged in email, chat and web browsing.  It presents the results of a pilot user study of the PyFlag forensic tool.  Finally, it presents a technique to use software to do a preliminary analysis on media and provide a human readable report to the examiner.  The goal of the technique is to perform rapid triaging of media and allow the human examiner to better prioritize man hours towards media with high return on investment.
; [http://portal.acm.org/citation.cfm?doid=1368506.1368519 The impact of full disk encryption on digital forensics], ACM SIGOPS Operating Systems Review archive, Volume 42 ,  Issue 3  (April 2008) , Pages 93-98 
:The integration of strong encryption into operating systems is creating challenges for forensic examiners, potentially preventing us from recovering any digital evidence from a computer. Because strong encryption cannot be circumvented without a key or passphrase, forensic examiners may not be able to access data after a computer is shut down, and must decide whether to perform a live forensic acquisition. In addition, with encryption becoming integrated into the operating system, in some cases, virtualization is the most effective approach to performing a forensic examination of a system with FDE. This paper presents the evolution of full disk encryption (FDE) and its impact on digital forensics. Furthermore, by demonstrating how full disk encryption has been dealt with in past investigations, this paper provides forensics examiners with practical techniques for recovering evidence that would otherwise be inaccessible.
; [http://www.ssddfj.org/papers/SSDDFJ_V2_1_Turnbull.pdf Forensic Investigation of the Nintendo Wii: A First Glance], Dr. Benjamin Turnbull, SMALL SCALE DIGITAL DEVICE FORENSICS JOURNAL, VOL. 2, NO. 1, JUNE 2008 ISSN# 1941-6164
: The closed nature of the Wii makes it a challenging game console for forensic analysis. This article takes a first look at the platform, discussing the various places where forensically interesting information may be hidden. There's also a reference to an interesting article about how the ability of wimotes to move avatars from one system to another documents a woman's affair while her husband was serving in Iraq.
; [http://www.waset.org/pwaset/v26/v26-6.pdf Data Acquisition from Cell Phone using Logical Approach], Keonwoo Kim, Dowon Hong, Kyoil Chung, and Jae-Cheol Ryou, PROCEEDINGS OF WORLD ACADEMY OF SCIENCE, ENGINEERING AND TECHNOLOGY VOLUME 26 DECEMBER 2007 ISSN 1307-6884
: This article discusses three approaches for acquiring data from cell phones: physically removing the flash RAM chips and reading them directly; reading the data out using the [[JTAG]] interface, and running software on the cell phone to extract the files at a logical level. The authors have built a logical extraction system and are working on a system based on JTAG.
; [[Media:Thesis-David-Nadeau.pdf|Semi-Supervised Named Entity Recognition]]: Learning to Recognize 100 Entity Types with Little Supervision, David Nadeau, PhD Thesis, University of Ottawa, 2007.
: Named Entity Recognition is the process of analyzing text documents and automatically identifying the Who, What, Where and Whens. David Nadeau's thesis presents a novel approach which bootstraps a named entity recognizer using semi-structured documents on the web. Few forensic tools use NER today, but that may well change in the future. What makes this thesis so interesting to read is that it also has a history of the last 20 years or so of the field. Highly recommended.
; [http://portal.acm.org/citation.cfm?id=1363239 Advanced JPEG carving], Michael I. Cohen, Proceedings of the 1st international conference on Forensic applications and techniques in telecommunications, information, and multimedia and workshop
: Michael I. Cohen presents a fully automated carver which can carve fragmented JPEGs using typical fragmentation patterns. (Cohen argues the the DFRWS carving challenges do not represent typical fragmentation patterns.)
; [http://www.cs.umass.edu/~miklau/pubs/sigmod2007LMS/stahlberg07forensicDB.pdf Threats to Privacy in the Forensic Analysis of Database Systems]
: Patrick Stahlberg, Gerome Miklau, and Brian Neil Levine
: Proceedings of the 2007 ACM SIGMOD international conference on Management of data table of contents
: Beijing, China.
: This paper looks at residual data left behind in databases after DELETE, UPDATE, and VACUUM operations. The authors show that residual data is a real issue in databases, and that it's pretty easy to modify a database so that no residual data is left behind. MySQL with MyISM tables has clean delete, but InnoDB does not. Very much worth reading.
; [http://www.usenix.org/events/sec08/tech/halderman.html Lest We Remember: Cold Boot Attacks on Encryption Keys]
: J. Alex Halderman, Princeton University; Seth D. Schoen, Electronic Frontier Foundation; Nadia Heninger and William Clarkson, Princeton University; William Paul, Wind River Systems; Joseph A. Calandrino and Ariel J. Feldman, Princeton University; Jacob Appelbaum; Edward W. Felten, Princeton University
: [http://www.usenix.org/events/sec08/ USENIX Security '08 Refereed Paper]
: Awarded Best Student Paper
: Increasingly memory analysis is of interest in forensic research---both because new malware only resides in memory, and because memory analysis is frequently the only way for analysts to get the keys that are used to protect cryptographic file systems. In this paper the authors show that cryptographic keys in memory are vulnerable to exploitation ''after the computer is turned off.'' The authors show that the contents of dynamic RAM are retained seconds, and sometimes minutes, after power is turned off. By chilling the memory the data can be retained as long as necessary. And while most laptops wipe their memory when they reboot, the authors show that the chilled memory can be moved from one laptop that wipes to another laptop that does not wipe. Finally, the authors show that it is possible to find the cryptographic keys in memory and correct random bit errors by using the AES key schedule as an error-correction code. The authors demonstrate an attack USB stick which reboots a computer protected with BitLocker, finds the cryptographic keys, and then allows access to the cleartext information on the disk.
; The [http://cups.cs.cmu.edu/soups/2008  Symposium on Usable Privacy and Security (2008)] concluded this past week in Pittsburgh, PA. One paper that appeared which is interesting to the network forensics crowd is [http://cups.cs.cmu.edu/soups/2008/proceedings/p107Werlinger.pdf The Challenges of Using an Intrusion Detection System: Is It Worth the Effort?], by Rodrigo Werlinger, Kirstie Hawkey, Kasia Muldner, Pooya Jaferian and Konstantin Beznosov. [http://cups.cs.cmu.edu/soups/2008/slides/hawkey_soups.ppt slides]
: In this article, the authors conducted interviews with 9 IT security practitioners who have worked with IDSs performed ethnographic observations within an organization that was deploying a new IDS. They found that security practitioners were heavily divided on the value of the IDS, and learned that the an IDS really only generates value if the network is well-understood before the IDS is deployed.
;The [http://www.utica.edu/academic/institutes/ecii/ijde/ International Journal of Digital Evidence] is one of two publications by the [http://www.utica.edu/academic/institutes/ecii/ Electronic Crime Institute (ECI)] at Utica College. Current and previous issues are available online.
: The current Fall 2007 issue has an interesting article [http://www.utica.edu/academic/institutes/ecii/publications/articles/1C33DF76-D8D3-EFF5-47AE3681FD948D68.pdf Mobile Phone Forensics Tool Testing: A Database Drive Approach] by Baggili, Mislan, and Rogers at Purdue University. Given that phones are increasingly a primary source of forensic information in many cases, we need to be sure that the tools that are used for forensic analysis present data that is accurate and repeatable. Unfortunately they frequently aren't because of there are so many different kinds of phones on the market and the forensic tools lag far behind the market.
@article{title="Mobile Phone Forensics Tool Testing: A Database Driven Approach",
author="Ibrahim M. Baggili and Richard Mislan and Marcus Rogers",
journal="International Journal of Digital Evidence",
abstract="The Daubert process used in the admissibility of evidence contains major guidelines
applied in assessing forensic procedures, two of which are testing and error rates. The
Digital Forensic Science (DFS) community is growing and the error rates for the forensic
tools need to be continuously re-evaluated as the technology changes. This becomes
more difficult in the case of mobile phone forensics, because they are proprietary. This
paper discusses a database driven approach that could be used to store data about the
mobile phone evidence acquisition testing process. This data can then be used to
calculate tool error rates, which can be published and used to validate or invalidate the
mobile phone acquisition tools. "
  publisher="DFRWS 2008",
  author="Anandabrata Pal and Taha Sencar and Nasir Memon",
  title="Detecting File Fragmentation Point Using Sequential Hypothesis Testing",
  abstract="Abstract—File carving is a technique whereby data files are
extracted from a digital device without the assistance of file
tables or other disk meta-data. One of the primary challenges in
file carving can be found in attempting to recover files that are
fragmented. In this paper, we show how detecting the point of
fragmentation of a file can benefit fragmented file recovery. We
then present a sequential hypothesis testing procedure to identify
the fragmentation point of a file by sequentially comparing
adjacent pairs of blocks from the starting block of a file until
the fragmentation point is reached. By utilizing serial analysis we
are able to to minimize the errors in detecting the fragmentation
points. The performance results obtained from the fragmented
test-sets of DFRWS 2006 and 2007 show that the method can be
effectively used in recovery of fragmented files.
clear that recovery of fragmented files is a critical problem in
forensics. ",
This DFRWS 2008 article presents an improved approach for carving fragmented JPEGs using sequential hypothesis testing. According to the authors, "The technique begins with a header block identifying the start of a file and then attempts to validate via SHT each subsequent block following the header block. The fragmentation point is identified when SHT identifies a block as not belonging to the file. By utilizing this technique, we are able to correctly and efficiently recover JPEG images from the DFRWS 2006 [1] and 2007 [2] test sets even in the presence of tens of thousands of blocks and files fragmented into 3 or more parts. The bifragment gap carving technique enhanced with SHT allows us to improve the performance result of DFRWS 2006 challenge test-sets,
although the technique cannot be used for DFRWS 2007. We then show how Parallel Unique Path enhanced with SHT is able to recover all fragmented JPEGs from DFRWS 2006 and all recoverable JPEGs from 2007 challenge test-sets. As far as we are aware, no other automated technique can recover multi-fragmented JPEGs from the DFRWS 2007 test set."
  publisher="Taylor & Francis",
  journal="Journal of Digital Forensic Practice", 
  author="Yoginder Singh Dandass and Nathan Joseph Necaise and Sherry Reede Thomas",
  title="An Empirical Analysis of Disk Sector Hashes for Data Carving",
  abstract="Discovering known illicit material on digital storage devices is an important component of a digital forensic investigation. Using existing data carving techniques and tools, it is typically difficult to recover remaining fragments of deleted illicit files whose file system metadata and file headers have been overwritten by newer files. In such cases, a sector-based scan can be used to locate those sectors whose content matches those of sectors from known illicit files. However, brute-force sector-by-sector comparison is prohibitive in terms of time required. Techniques that compute and compare hash-based signatures of sectors in order to filter out those sectors that do not produce the same signatures as sectors from known illicit files are required for accelerating the process.
This article reports the results of a case study in which the hashes for over 528 million sectors extracted from over 433,000 files of different types were analyzed. The hashes were computed using SHA1, MD5, CRC64, and CRC32 algorithms and hash collisions of sectors from JPEG and WAV files to other sectors were recorded. The analysis of the results shows that although MD5 and SHA1 produce no false-positive indications, the occurrence of false positives is relatively low for CRC32 and especially CRC64. Furthermore, the CRC-based algorithms produce considerably smaller hashes than SHA1 and MD5, thereby requiring smaller storage capacities. CRC64 provides a good compromise between number of collisions and storage capacity required for practical implementations of sector-scanning forensic tools.",
Authors Dandass ''et. al'' analyzed 528 million sectors from 433,630 unique files. They computed the CRC32, CRC64, MD5 and SHA-1 of each sector. Not surprisingly, they find that the MD5 and SHA-1s of the sectors are different if the sectors are different. They find 94 CRC64 collisions and 30 million CRC32 collisions. The conclusion is that, if you are search for a single sector or building a database of single sector hashes, you are better off building a database of CRC64s because they are easier to store and dramatically faster to calculate than the traditional hash functions, and they are nearly as accurate.

Latest revision as of 06:30, 8 August 2013