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Skype Source Code Leaked, Experts Say It’s Old Reverse Engineering Project July 18th, 2012, 11:50 GMT · By Eduard Kovacs An Anonymous-affiliated hacker that goes by the name of Stun, claims to have leaked Skype’s source code and the de-obfuscated binaries as a form of protest against the “governmental backdoor.” “After Microsoft acquiring Skype for 8.5 billion dollars and proceeding to add back doors for government to the program, the software has been hacked and it's source code released,” Stun wrote next to links that point to three files hosted on The Pirate bay. The hacktivist motivates his actions by pointing to articles that show that Skype is utilized as a medium to spread viruses onto the computers of activists from Syria. However, experts state that the source code published by the hacker is actually the one leaked some time ago by a researcher who reverse engineered the Windows binaries. Security researcher Janne Ahlberg says that the same files have been distributed already earlier this year. Furthermore, he believes that they’re part of the reverse engineering case in which Skype pursued the researcher, accusing him of “unauthorized use of their application for malicious activities.” “I managed to get a copy of the file ‘skype55_59_deobfuscated’ from May. It is not Skype source code, but a reverse engineered version of the Windows binaries. The tool used in reverse engineering seems to be IDA disassembler/debugger,” Ahlberg told Softpedia in an email. “Stun's tweet seems to be based on this reverse engineering project,” he concluded. So there you have it. It seems that this is nothing more than a classic case of a hacker that takes the work of others and publishes it as his own. Sophos researchers have analyzed the reverse engineering case of the Skype protocol. Head of Technology Paul Ducklin presented a detailed scenario of what would happen if the popular application’s source code actually got leaked. http://news.softpedia.com/news/Skype-Source-Code-Leaked-Experts-Say-It-s-Old-Reverse-Engineering-Project-281892.shtml

Cum s? m?re?ti pozele, f?r? s? pierzi detaliile Aurelian Mihai - 19 iul 2012 Procedeul v?zut pân? acum doar în filmele poli?iste, în care specialistul laboratorului de investiga?ii reconstruia ca prin minune orice imagine neclar? ap?sând câteva taste în fa?a unui PC extrem de sofisticat, ob?inând în câteva secunde portretul unui suspect sau num?rul de înmatriculare al unui vehicul, este acum realitate ?i aproape la îndemâna oricui. În lumea real? procedeul se nume?te super-resolu?ion ?i poate fi abordat în dou? moduri diferite. Prima abordare presupune existen?a unei secven?e video din care s? prelu?m mai multe imagini succesive care surprind acela?i obiect, urmând ca un filtru software s? extrag? cât mai multe detalii cu putin?? din care s? construiasc? o singur? imagine mai clar?. A doua abordare func?ioneaz? cu o singur? imagine surs? ?i presupune folosirea unor tehnici de procesare avansate, prin care se analizeaz? con?inutul imaginii c?utând elemente similare, care pot fi combinate pentru reconstruirea detaliilor neclare. Pentru a în?elege mai bine acest procedeu, imagina?i-v? o poz? abia descifrabil? cu un peisaj din ora?, în care apar cl?diri, str?zi asfaltate, un afi? cu text aproape ilizibil, etc. Majoritatea obiectelor din imagine au un aspect distinctiv, ce urmeaz? un anumit tipar: textura asfaltului, liniile c?r?mizilor de pe peretele c?dirii, forma literelor de pe afi?. În majoritatea cazurilor, detaliile abia vizibile urmeaz? un tipar repetitiv, dar cu varia?ii subtile la nivel de sub-pixel ?i dimensiunea elementelor individuale, în func?ie de cum sunt pozi?ionate obiectele în spa?iul tridimensional. Filtrul super-resolu?ion separ? din imagine cele mai reprezentative detalii, generând un veritabil puzzle cu modele de texturi , care serve?te apoi la reconstruc?ia detaliilor estompate din imaginea surs?. Pe scurt, cu procedeul super-resolution putem transforma o poz? neclar? sau de rezolu?ie mic?, într-o imagine mai bine detaliat? , redat? la o rezolu?ie mai mare decât originalul. Tehnologia super-resolution, dezvoltat? de Institutul Weizmann de cercet?ri ?tiin?ifice,func?ioneaz? atât cu imagini statice dar ?i secven?e video, dând cele mai bune rezultate cu scenele care con?in multe detalii cu tipar repetitiv. Tehnica Weizmann func?ioneaz? desp?r?ind mai întâi imaginea original? într-un puzzle de imagini mai mici, fiecare m?surând doar câ?iva pixeli. Elementele individuale ale acestui puzzle sunt comparate între ele c?utând detalii cu aspect asem?n?tor. Atunci când sunt g?site dou? sau mai multe texturi asem?n?toare, este posibil? recompunerea &unei texturi mai clare decât originalul. Toate fragmentele de texturi rezultate sunt folosite apoi la reconstruc?ia imaginii originale. Procedeul nu este chiar perfect ?i poate genera detalii false, percepute ca artefacte în imagine ?i vizibile mai ales la reconstruc?ia detaliilor fine, abia vizibile în imaginea surs?. Tehnologia super-resolu?ion se prezint? ca o modalitate mai avansat? de m?rire a imaginilor, cu rezultate mult superioare calitativ fa?? de tehnicile clasice implementate în aplica?iile de editare imagine. O a doua utilitate poate fi în domeniul cre?terii eficien?ei tehnicilor de compresie video ?i imagine. Din p?cate procedeul super-resolu?ion are ?i un inconvenient major: este foarte intensiv din punct de vedere al cerin?elor de procesare ?i prea lent pentru a fi aplicat în timp real (de exemplu pentru îmbun?t??irea imaginilor afi?ate în browserul web sau filme pe YouTube). Exist? totu?i speran?e ca procesarea în timp real s? fie în cele din urm? posibil? cu ajutorul acceler?rii prin GPU, folosind una sau mai multe pl?ci video performate. Sursa: Cum s? m?re?ti pozele, f?r? s? pierzi detaliile

Creator: Matt Briggs License: Creative Commons: Attribution, Share-Alike (Creative Commons — Attribution-ShareAlike 3.0 Unported — CC BY-SA 3.0) Lab Requirements: Windows system with IDA Pro (Free 5.0 is acceptable). Microsoft Visual Studio 2008 redistributable package. Class Textbook: Reversing: Secrets of Reverse Engineering by Eldad Eilam. Recommended Class Duration: 2 days Creator Available to Teach In-Person Classes: Yes Author Comments: Throughout the history of invention curious minds have sought to understand the inner workings of their gadgets. Whether investigating a broken watch, or improving an engine, these people have broken down their goods into their elemental parts to understand how they work. This is Reverse Engineering (RE), and it is done every day from recreating outdated and incompatible software, understanding malicious code, or exploiting weaknesses in software. In this course we will explore what drives people to reverse engineer software and the methodology and tools used to do it. Topics include, but are not limited to: •Uses for RE •The tricks and pitfalls of analyzing compiled code •Identifying calling conventions •How to navigate x86 assembly using IDA Pro •Identifying Control Flows •Identifying the Win32 API •Using a debugger to aid RE •Dynamic Analysis tools and techniques for RE During the course students will complete many hands on exercises. This class will serve as a prerequisite for a later class on malware analysis. Before taking this class you should take Introduction to Intel x86 or have equivalent knowledge. All Material (TiddlyWiki (html+javascript) & analyzed binaries (PE)) 8:33:02 total sursa: http://opensecuritytraining.info/IntroductionToReverseEngineering.html

Creator: Corey K. License: Creative Commons: Attribution, Share-Alike (Creative Commons — Attribution-ShareAlike 3.0 Unported — CC BY-SA 3.0) Lab Requirements: Linux VM provided below. Or any Linux VM with the provided vulnerable software examples installed. Class Textbook: The Shellcoder’s Handbook by Chris Anley et al. Recommended Class Duration: 2 days Creator Available to Teach In-Person Classes: Yes Author Comments: Software vulnerabilities are flaws in program logic that can be leveraged by an attacker to execute arbitrary code on a target system. This class will cover both the identification of software vulnerabilities and the techniques attackers use to exploit them. In addition, current techniques that attempt to remediate the threat of software vulnerability exploitation will be discussed. This will be a lab driven class where specific software vulnerability types in particular environments are discussed and then exploited in a lab setting. Examples of lab components of the class as well as specific topics covered include: •Shellcode development •Stack overflow exploitation •Heap overflow exploitation •Static source code analysis •Defeating non-executable stack protection The class will help students be more aware of the specific details and mechanisms of software exploits we see in the wild. This knowledge will enable the students to better analyze their own software for vulnerabilities in an effort to produce more secure code. Slides: ppt odp pdf Exercise Code (.tgz) 9:38:54 totalsursa: http://opensecuritytraining.info/IntroductionToSoftwareExploits.html

edit: atom 128 -> base 64