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Secure Programming II: the Revenge
Secure Programming II: The Revenge Lecture for 5/11/20 (slides from Prof. Dooley) CS 330 Secure Programming 13 Administrivia • Seminar on Tuesday (5/12, 7pm): Tech Career Tips and Strategies for International Students (Extra credit!) • HW 6 (password cracking) due Thursday night CS 330 Secure Programming Recall: Secure programming problems • Buffer overflow • Resource exhaustion • Incomplete mediation (checking valid data) • Time-of-check to time-of-use errors • Other race conditions • Numeric over/underflow • Trust in general (users and privileges, environment variables, trusting other programs) CS 330 Secure Programming 15 General principles of secure software • Simplicity is a virtue • If code is complex, you don’t know if it’s right (but it probably isn’t) • In a complex system, isolate the security-critical modules. Make them simple • Modules should have a clean, clear, precisely defined interface CS 330 Secure Programming 16 General principles of secure software - 2 • Reliance on global state is bad (usually) • Reliance on global variables is bad (usually) • Use of explicit parameters makes input assumptions explicit • Validate all input data • Don’t trust tHe values of environment variables • Don’t trust library functions tHat copy data CS 330 Secure Programming 17 Buffer Overflows CS 330 Secure Programming Buffer Overflow • 1988: Morris worm exploits buffer overflows in fingerd to infect 6,000 Unix servers • 2001: Code Red exploits buffer overflows in IIS to infect 250,000 servers – Single largest cause of vulnerabilities in CERT advisories – Buffer overflow threatens Internet- WSJ(1/30/01) • CERT advisory dated 12 April 2005 notes several vulnerabilities in MS Windows, including three buffer overflows in Explorer, MSN Messenger, and MS Exchange Server. -
INNOV-04 the SANS Top 20 Internet Security Vulnerabilities (And What It Means to Openedge™ Applications)
INNOV-04 The SANS Top 20 Internet Security Vulnerabilities (and what it means to OpenEdge™ Applications) Michael Solomon, CISSP PMP CISM Solomon Consulting Inc. www.solomonconsulting.com (Thanks to John Bruggeman for presentation input) What is the SANS Top 20 SANS and FBI / NIPC created list in 2000 10 Windows vulnerabilities 10 Unix vulnerabilities – 90% of all computer security breaches are caused by known vulnerabilities (Gartner Group 2002) Tools to detect and repair the Top 20 – Many referenced tools help detect and repair many more than the Top 20 Vulnerabilities INNOV-04, SANS Top 20 Security Vulnerabilities 2 How do these vulnerabilities affect OpenEdge applications? OpenEdge is not specifically mentioned – Many vulnerabilities on the list still apply to OpenEdge application systems – Interpret each vulnerability in terms of your system Any system vulnerability affects your OpenEdge application INNOV-04, SANS Top 20 Security Vulnerabilities 3 Windows Top 10 – www.sans.org/top20/#w1 1. Web Servers and Services 2. Workstation Service 3. Windows Remote Access Services (not RAS) 4. Microsoft SQL Server 5. Windows Authentication 6. Web Browsers 7. File-Sharing Applications 8. LSAS Exposures 9. Mail Client 10. Instant Messaging INNOV-04, SANS Top 20 Security Vulnerabilities 4 W1: Web Servers and Services Risks of default installations – Denial of service (DoS) – Compromise server and data – Execution of arbitrary commands All web servers are affected, including – Internet Information Server (IIS) • Even though IIS 6.0 is ‘secure -
Pest Control: Taming the Rats
RESEARCH pest control: taming the rats Authors Remote Administration Tools (RATs) allow a Shawn Denbow remote attacker to control and access the Twitter: @sdenbow_ system. In this paper, we present our analysis of Email: [email protected] their protocols, explain how to decrypt their Jesse Hertz traffic, as well as present vulnerabilities we have Twitter: @hectohertz found. Email: [email protected] Introduction As 2012 Matasano summer interns, we were tasked with running a research project with a couple criteria: • It should be something we are both interested in. • We should be able to present our research for the company at the end of our internship. However, on completion, we decided that it would be best if we made our findings public. With John Villamil, our advisor, we decided that given our interest in low-level analysis, we should analyze Remote Administration Tools (RATs). RATs have recently seen media attention due to their use by oppressive governments in spying on activists and other “dissidents”. We felt this to be a perfect project. Remote Administration Tools are pieces of software which, once installed on a victim’s computer allow a remote user to control and access the system. RATs can be used legitimately by system administrators, or they can be used maliciously. There are a variety of methods by which they are installed on a computer: Various social engineering tactics can be employed to get a user to open the executable, they can be bundled with other pieces of software, they can be installed as the payload of a virus or worm, or they can be installed after an attacker gains access to a system through an exploit. -
Chapter 11 – Buffer Overflow
Computer Security: Principles and Practice ChapterChapter 1111 –– BufferBuffer OverflowOverflow First Edition by William Stallings and Lawrie Brown Lecture slides by Lawrie Brown Buffer Overflow • a very common attack mechanism – from 1988 Morris Worm to Code Red, Slammer, Sasser and many others • prevention techniques known • still of major concern due to – legacy of widely deployed buggy – continued careless programming techniques 2 Buffer Overflow Basics • caused by programming error • allows more data to be stored than capacity available in a fixed sized buffer – buffer can be on stack, heap, global data • overwriting adjacent memory locations – corruption of program data – unexpected transfer of control – memory access violation – execution of code chosen by attacker 3 int main( int argc, char * argv[]) { int valid = FALSE; Buffer char str1[8]; char str2[8]; Overflow next_tag(str1); gets(str2); Example if (strncmp(str1, str2, 8) == 0) valid = TRUE; printf("buffer1: str1(%s), str2(%s), valid(%d)\n", st r1, str2, valid); } $ cc -g -o buffer1 buffer1.c $ ./buffer1 START buffer1: str1(START), str2(START), valid(1) $ ./buffer1 EVILINPUTVALUE buffer1: str1(TVALUE), str2(EVILINPUTVALUE), valid(0) $ ./buffer1 BADINPUTBADINPUT buffer1: str1(BADINPUT), str2(BADINPUTBADINPUT), valid(1) 4 Buffer Memory Before After Contains Address gets(str2) gets(str2) Value of Overflow . Example bffffbf4 34fcffbf 34fcffbf argv 4 . 3 . bffffbf0 01000000 01000000 argc . bffffbec c6bd0340 c6bd0340 return . @ . @ addr bffffbe8 08fcffbf 08fcffbf old base . ptr bffffbe4 00000000 01000000 valid . bffffbe0 80640140 00640140 . d . @ . d . @ bffffbdc 54001540 4e505554 str1[4-7] T . @ N P U T bffffbd8 53544152 42414449 str1[0-3] S T A R B A D I bffffbd4 00850408 4e505554 str2[4-7] . -
Computer Security 03
Computer Security 03. Program Hijacking & Code Injection Paul Krzyzanowski Rutgers University Spring 2019 September 25, 2019 CS 419 © 2019 Paul Krzyzanowski 1 Top vulnerability concerns for 2019 MITRE, a non-profit organization that manages federally-funded research & development centers, publishes a list of top security weaknesses Rank Name Score 1 Improper Restriction of Operations within the Bounds of a Memory Buffer 75.56 2 Cross-site Scripting 45.69 3 Improper Input Validation 43.61 4 Information Exposure 32.12 5 Out-of-bounds Read 26.53 6 SQL Injection 24.54 7 Use After Free 17.94 8 Integer Overflow or Wraparound 17.35 9 Cross-Site Request Forgery (CSRF) 15.54 10 14.10 Improper Limitation of a Pathname to a Restricted Directory ('Path Traversal') https://cwe.mitre.org/top25/archive/2019/2019_cwe_top25.html September 25, 2019 CS 419 © 2019 Paul Krzyzanowski 2 Hijacking Getting software to do something different from what the user or developer expected Examples: • Redirect web browser to a malicious site • Change DNS (IP address lookup) results • Change search engine • Change search paths to load different libraries or have different programs run • Intercept & alter messages Code injection Getting a program to process data in a way that it changes the execution of a program September 25, 2019 CS 419 © 2019 Paul Krzyzanowski 3 Bugs and mistakes • Most attacks are due to – Social engineering: getting a legitimate user to do something – Or bugs: using a program in a way it was not intended • Attacked system may be further weakened because -
Adwind a Cross Platform
ADWIND A CROSSPLATFORM RAT REPORT ON THE INVESTIGATION INTO THE MALWAREASASERVICE PLATFORM AND ITS TARGETED ATTACKS Vitaly Kamluk, Alexander Gostev February 2016 V. 3.0 #TheSAS2016 #Adwind CONTENTS Executive summary ..................................................................................................... 4 The history of Adwind ................................................................................................ 5 Frutas RAT ................................................................................................................. 5 The Adwind RAT ..................................................................................................... 11 UNRECOM ................................................................................................................ 17 AlienSpy ..................................................................................................................... 24 The latest reincarnation of the malware ............................................................. 28 JSocket.org: malware-as-a-service ................................................................. 28 Registration .............................................................................................................. 29 Online malware shop ........................................................................................... 30 YouTube channel .................................................................................................... 32 Profitability .............................................................................................................. -
Stack Buffer Overflow
1 Stack Buffer Overflow Chengyu Song Slides modified from Dawn Song 2 Infection vectors of malware • Human assistant, unknowingly • Exploiting vulnerabilities • We see the term "buffer overflow" several time, but • What is buffer overflow? • Why it would allow attackers/malware to get into the system? 3 Software security • Surround a central topic vulnerabilities • What is a vulnerability? • What types of vulnerabilities are there? • How do we find vulnerabilities? • How do we fix vulnerabilities? • How do we exploit vulnerabilities? • How do we prevent exploits? 4 Software vulnerability A vulnerability is a weakness in a software that could allow an attacker to compromise the information assurance of the system. -- Wikipedia “• Weakness: bugs, configure errors, etc. • Information assurance: confidentiality, integrity, availability, etc. 5 Exploit An exploit is a piece of input that takes advantage of a vulnerability in order to cause unintended behavior -- Wikipedia “• Input: file, data, program, etc. • Unintended behavior: arbitrary code execution, privilege escalation, denial- of-service (DoS), information leak, etc. 6 Putting things together --OWASP 7 Popular types of vulnerabilities • Memory corruption • Buffer overflow, use-after-free, uninitialized data access, etc. • Improper input sanitation (a.k.a. injection attacks) • SQL injection, command injection, cross-site script (XSS), etc. • Insufficient Authentication/authorization • Missing checks, hardcoded credential, backdoor, etc. • Incorrect use of crypto primitives • Weak primitives (encryption, -
Growth and Commoditization of Remote Access Trojans
30 September - 2 October, 2020 / vblocalhost.com GROWTH AND COMMODITIZATION OF REMOTE ACCESS TROJANS Veronica Valeros & Sebastian García Czech Technical University in Prague, Czech Republic [email protected] [email protected] www.virusbulletin.com GROWTH AND COMMODITIZATION OF REMOTE ACCESS TROJANS VALEROS & GARCÍA ABSTRACT Remote access trojans (RATs) are an intrinsic part of traditional cybercriminal activities, and they have also become a standard tool in advanced espionage attacks and scams. There have been significant changes in the cybercrime world in terms of organization, attacks and tools in the last three decades, however, the overly specialized research on RATs has led to a seeming lack of understanding of how RATs in particular have evolved as a phenomenon. The lack of generalist research hinders the understanding and development of new techniques and methods to better detect them. This work presents the first results of a long-term research project looking at remote access trojans. Through an extensive methodological process of collection of families of RATs, we are able to present an analysis of the growth of RATs in the last 30 years. Through a closer analysis of 11 selected RATs, we discuss how they have become a commodity in the last decade. Finally, through the collected information we attempt to characterize RATs, their victims, attacks and operators. Preliminary results of our ongoing research have shown that the number of RATs has increased drastically in the past ten years and that nowadays RATs have become standardized commodity products that are not very different from each other. INTRODUCTION Remote access software is a type of computer program that allows an individual to have full remote control of the device on which the software is installed. -
Stack Based Buffer Overflows and Protection Mechanisms.Pdf
Buffer Overflows. Protection Mechanisms. Stack Based Buffer Overflows and Protection Mechanisms. Software Security January 2008 Igor Yuklyanyuk 1 Outline ■ Buffer Overflow Introduction ■ What is a buffer overflow? ■ What is a ShellCode? ■ Exploitation ■ ASLR – Address Space Layout Randomization ■ Non-Executable Stack ■ Canaries 2 Part One What Is a Buffer Overflow ??? 3 What is a Buffer Overflow ■ A class of vulnerability caused by a bug in application ■ Most bugs in the 90's and early 00's were buffer overflows ■ May be exploited by attacker to gain control of the system 4 What is a Buffer Overflow ■ Buffer Overflow is a program condition where data is written past allocated buffer (e.g. a string buffer) ■ Data copied past allocated buffer affects other bits of the program ■ Buffer Overflow may occur on stack or heap portion of memory ■ We are only concern with stack overflows ■ Not All Overflows are exploitable 5 What is a Buffer Overflow ■ Stack is a LIFO Data Structure ■ New stack frame is Created every function Call (runtime) ■ Execution is continued at Return Address after function completion ■ On x86 Stack grows upwards while Memory Addressing grows Downwards 6 What is a Buffer Overflow 7 What is a Buffer Overflow 8 What is a Buffer Overflow 9 What is a ShellCode ■ Instead of breaking the program attacker wants to take control ■ ShellCode is the code that is executed upon successful attack ■ Performs specific tasks, such as shell execution (hence ShellCode), connect to attacker controlled host, log deletion etc. ■ Restricted in -
Lecture 18: Buffer Overflows 1 a Program to Exploit
CS342 Computer Security Handout # 21 Prof. Lyn Turbak April 4, 2016 Wellesley College Lecture 18: Buffer Overflows Sources Jon Erickson, Hacking: The Art of Exploitation, Chapter 0x300. Aleph One, \Smashing the Stack for Fun and Profit” (can be found at http://cs.wellesley.edu/ ~cs342/papers/stack-smashing.pdf). 1 A Program to Exploit We begin with a simple program to exploit: /* Contents of ~cs342/download/overflow/vuln.c */ #include <stdio.h> // Header file that includes the type of printf #include <string.h> // Header file that include the type of strcpy int main (int argn, char** argv) { char buffer[100]; int i; long *addr_ptr; // a "long" is guaranteed to be a four-byte word strcpy(buffer, argv[1]); /* copies chars of argv[1] to buffer w/o bounds checking */ addr_ptr = (long *) buffer; for (i = 0; i < 35; i++) { printf("%02i:%08x:%08x\n", /* %08x displays 8 hex chars */ i, (unsigned int) addr_ptr, (unsigned int) *addr_ptr); addr_ptr++; } } The statement strcpy(buffer, argv[1]); copies the characters in argv[1] to buffer without any sort of bounds checking. So if there are more than 100 characters, it will start overwriting the stack after the end of the space allocated for buffer. The program also displays 35 words of memory starting with buffer = buffer[0]. Of course, a program wouldn't normally do this, but we include it to help us understand the exploit. We compile vuln.c as user lynux and make it setuid to make things interesting: lynux@cs342-ubuntu-1:~/overflow\$ gcc -o vuln -fno-stack-protector -z execstack vuln.c lynux@cs342-ubuntu-1:~/overflow\$ chmod 4755 vuln The gcc compilation flags -fno-stack-protector and -z execstack disable protections that would otherwise guard against the stack buffer overflow attacks we will be launching against vuln. -
Counter-Measures Against Stack Buffer Overflows in GNU/Linux Operating Systems
Available online at www.sciencedirect.com ScienceDirect Procedia Computer Science 83 ( 2016 ) 1301 – 1306 The International Workshop on Parallel Tasks on High Performance Computing (THPC-2016) Counter-measures against stack buffer overflows in GNU/Linux operating systems. Erick Leona, Stefan D. Brudaa* aBishop's University, 2600 College St., Sherbrooke QC, J1M 1Z7, Canada Abstract We address the particular cyber attack technique known as stack buffer overflow in GNU/Linux operating systems, which are widely used in HPC environments. The buffer overflow problem has been around for quite some time and continues to be an ever present issue. We develop a mechanism to successfully detect and react whenever a stack buffer overflow occurs. Our solution requires no compile-time support and so can be applied to any program, including legacy or closed source software for which the source code is not available. This makes it especially useful in HPC environments where given their complexity and scope of the computing system, incidents like overflows might be difficult to detect and react to accordingly. ©© 20162016 The The Authors. Authors. Published Published by byElsevier Elsevier B.V. B.V. This is an open access article under the CC BY-NC-ND license (Peehttp://creativecommons.org/licenses/by-nc-nd/4.0/r-review under responsibility of the Conference). Program Chairs. Peer-review under responsibility of the Conference Program Chairs Keywords: Buffer overflow; Stack; GNU/Linux; ptrace. 1. Introduction Most HPC systems run some variant of the GNU/Linux operating system, such as the CLUMEQ in Quebec, which uses CentOS 6.3. Tackling security issues in GNU/Linux is therefore a priority for HPC applications. -
SYSTEMATIC METHODS for MEMORY ERROR DETECTION and EXPLOITATION HU HONG (B.Eng., Huazhong University of Science and Technology) A
SYSTEMATIC METHODS FOR MEMORY ERROR DETECTION AND EXPLOITATION HU HONG (B.Eng., Huazhong University of Science and Technology) A THESIS SUBMITTED FOR THE DEGREE OF DOCTOR OF PHILOSOPHY DEPARTMENT OF COMPUTER SCIENCE NATIONAL UNIVERSITY OF SINGAPORE 2016 DECLARATION I hereby declare that this thesis is my original work and it has been written by me in its entirety. I have duly acknowledged all the sources of information which have been used in the thesis. This thesis has also not been submitted for any degree in any university previously. HU HONG 13 January 2016 ACKNOWLEDGEMENTS I am grateful to have my PhD study in National University of Singapore. During this long journey, many people provided their generous supports and suggestions. Without them, I will not harvest so much, including this thesis. First, I thank my advisor, Prof. Zhenkai Liang, who leads me to the exciting topic of binary analysis and guides me to be a security researcher with his insight and experi- ence. Along the challenging journey, he always advised me to think questions at a high level and dive to deep technical details, with great patience and perseverance. Thanks to Prof. Prateek Saxena for insightful comments on several papers that constitute this thesis. I learned a lot from the discussion and collaboration with him. Thanks to several professors who gave me valuable feedback to my thesis: Prof. Abhik Roychoudhury, Prof. Roland Yap and Prof. Heng Yin. They have expanded my research view and help me find the shortcomings of my work. I am indebted to all of my collaborators for their hard working and strong support.