PPT-Buffer Overflow

CS 465 Slides by Kent Seamons and Tim van der Horst Last Updated Nov 11 2011 Buffer Overflow The most common security vulnerability Root cause Unsafe programming languages What areas of process memory are vulnerable to a buffer overflow. . Attacker’s goal. :. Take over target machine (e.g. web server). Execute arbitrary code on target by . hijacking application control flow. This lecture: three examples.. Buffer overflow attacks. Overflow Example. Dan Fleck. CS469 Security Engineering. Reference: . http://. www.thegeekstuff.com. /2013/06/buffer-overflow/ . Coming up: Buffer Overflows. 1. 1. Buffer Overflows. Buffer overflows occur when some sized portion of memory is overwritten with something bigger.. http://en.wikipedia.org/wiki/Stack_buffer_overflow. What is a stack buffer overflow?. Caused when a program writes more data to a buffer on the stack than what was initially allocated for the buffer. 15-213: Introduction to Computer Systems. Recitation 6, Oct 1, 2012. Alexander Malyshev (amalyshe). Section A, 10:30a – 11:20p, WeH 4623. Agenda. Buffer overflow. Writing a C program. Makefiles. Revision Control. Exploiting Software. Exploiting Software . The exploitation of software is one of the main ways that a users computer can be broken into. . It involves exploiting the software running on the users computer to do something that was not intended by the developer. . What is an Exploit?. An . exploit. . is any . input. (i.e., a piece of software, an argument string, or sequence of commands) that takes advantage of a bug, glitch or vulnerability in order to cause an attack. Dr. X. Metasploitable. Not everything is what it looks like. …. You opened a reverse shell with root priviledges. B. ut did you?. Metasploitable. There was a bug. You were root back on the kali VM not the . Chih. Hung Wang. Reference:. 1. B. Chess and J. West, Secure Programming with Static Analysis, Addison-Wesley, 2007.. 2. R. C. . Seacord. , Secure Coding in C and C , Addison-Wesley, 2006.. 1. Introduction (1). Solutions made from a weak acid plus a soluble ionic salt of the weak acid.. Solutions made from a weak base plus a soluble ionic salt of the weak base. Solutions made of weak acids plus a soluble ionic salt of the weak acid. modified from slides of . Lawrie. Brown. Buffer Overflow. a very common attack mechanism. first wide use by the Morris Worm in 1988. prevention techniques known. still of major concern. legacy of buggy code in widely deployed operating systems and applications. Stack. in the higher parts of memory. Grows down. Used when a . function is called. Data Area. Global variables . not . inizialited. . to zero. BSS [. Block. . Started. by Symbol. ]. Segment. Global variables . modified from slides of . Lawrie. Brown. Buffer Overflow. a very common attack mechanism. first wide use by the Morris Worm in 1988. prevention techniques known. still of major concern. legacy of buggy code in widely deployed operating systems and . Bogi Hansen, Karin M. H. Larsen, Steffen Olsen, Detlef Quadfasel, Kerstin Jochumsen, Svein Østerhus. Canonical value for. IFR-overflow: 1 Sv . IFR. Arctic Mediterranean. WV-overflow:. Western Valley overflow. Dan Fleck. CS469 Security Engineering. Reference: . http://. www.thegeekstuff.com. /2013/06/buffer-overflow/ . Coming up: Buffer Overflows. 1. 1. Buffer Overflows. Buffer overflows occur when some sized portion of memory is overwritten with something bigger..