Malicious Code Threat Model Code Survey of Malicious Code Prevention of CSH6 Chapter 16 Malicious Code Attacks “Malicious Code” Robert Guess & Eric Salveggio
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Topics Malicious Introduction Malicious Code Threat Model Code Survey of Malicious Code Prevention of CSH6 Chapter 16 Malicious Code Attacks “Malicious Code” Robert Guess & Eric Salveggio CSH6 Chapter 16: “Malicious Code” 1 Copyright © 2014 M. E. Kabay. All rights reserved. 2 Copyright © 2014 M. E. Kabay. All rights reserved. Introduction Malicious-Code Threat Model (1) Malicious code / logic ACTOR ACCESS ASSET ACTION OUTCOME Malware Hardware, software or firmware Actor: structured or unstructured threats intentionally included or inserted Individuals, organizations, nation-states in system for unauthorized purpose Access: allowed physical or logical path Classification may be difficult Asset: resource of interest Categories overlap because malware may have Action: execution of malicious code or logic multiple functions and attributes Outcome E.g., virus / worm / Trojan horse / spyware Intelligence, surveillance, reconnaissance Disruption of operations Some code may not be intended as malware by creators Destruction of assets Publicity for cause Context and intent determine whether code is Negative publicity against victim viewed as malicious 3 Copyright © 2014 M. E. Kabay. All rights reserved. 4 Copyright © 2014 M. E. Kabay. All rights reserved. Malicious Code Threat Model (2) Self-replicating Code Not inherently malicious Self-replicating Code Early experiments (1960s) Actors: Origin of Malicious had no evil intent Code Threats Darwin (1961) involved Actors: Structured Threats memory worms Actors: Unstructured Self-replicating code Threats Competition → resource exhaustion Access vs Action: Vector vs Payload 5 Copyright © 2014 M. E. Kabay. All rights reserved. 6 Copyright © 2014 M. E. Kabay. All rights reserved. Is a Beneficial Virus Is Writing Malware Illegal Possible? in US? Ideas for beneficial self-propagating code: No explicit law against writing malicious code Distribute antivirus programs No illegality even in sharing such code automatically through Internet among willing recipients Install patches on servers in networks Current efforts to define statutes Distribute useful information automatically Based on laws banning Consensus on Problems Preventing Use: possession of burglary tools (e.g., lock picks) What if there’s a bug or incompatibility in the self-propagating code? Require registration and licensing of locksmiths What if the patches are not appropriate for a specific Would treat malware and Trojans in same server or network? way What if the owner/user does No significant progress to date not see the patch as useful? 7 Copyright © 2014 M. E. Kabay. All rights reserved. 8 Copyright © 2014 M. E. Kabay. All rights reserved. Actors: Origin of Actors: Structured Threats Malicious Code Threats Well-funded, systematic Structured threats Industrial espionage, information operations, large- scale fraud & theft Nation-states Organized crime responsible for 90% malware Corporate criminals Extortionists target online gambling Organized crime Pump ‘n’ dump schemes cost $B Unstructured threats Industrial espionage using spyware growing Rogue actors; e.g., China major player Individuals Major source of attacks Script kiddies PRC PLA doctrine emphasizes asymmetric warfare using information technology Total government control over hacking 9 Copyright © 2014 M. E. Kabay. All rights reserved. 10 Copyright © 2014 M. E. Kabay. All rights reserved. Access vs Action: Actors: Unstructured Threats Vector vs Payload Random Vector Relatively limited Agent is avenue of access Does not target national Physical access via people who can enter security premises Relatively minor Network access via Web server, client systems, e-mail attachment, portable device (e.g., infected USB flash drive) Payload Function (action) inserted in system Malicious logic, remote access software, remote control software 11 Copyright © 2014 M. E. Kabay. All rights reserved. 12 Copyright © 2014 M. E. Kabay. All rights reserved. Survey of Malicious Code Virus Mechanisms Viruses Worms Boot sector: sector 0 of disk Trojans File infector: inserts JUMP instruction, adds code, returns to original location and Spyware & Adware continues loading Rootkits Macro virus: exploits weakness of MS Bots & Botnets scripting language in Word, Malicious Mobile Code PowerPoint, Excel, Access etc. 13 Copyright © 2014 M. E. Kabay. All rights reserved. 14 Copyright © 2014 M. E. Kabay. All rights reserved. Viruses (1) Viruses (2) Boot sector Program infectors 15 Copyright © 2014 M. E. Kabay. All rights reserved. 16 Copyright © 2014 M. E. Kabay. All rights reserved. 1995-1996: Early Macro Viruses (3) Viruses Macro MS-Word macro virus (concept) released Aug 95 MS-Word macro viruses reached more than half all infections in the wild by 2009 About 1000 types of macro viruses of all types known to date (Sep 2013) MS-Excel virus discovered June 96 Anti-virus available within days Spreading more slowly than Word macro viruses because of lower rate of exchange of spreadsheets 17 Copyright © 2014 M. E. Kabay. All rights reserved. 18 Copyright © 2014 M. E. Kabay. All rights reserved. 1999-03: Melissa Virus Viruses (4) Logic Bombs Friday 26 March: CERT-CC initial reports of fast-spreading new MS-Word macro virus Any malicious code, replicating or not, that Melissa written to infect Word documents delivers a payload as a result of a logic test (e.g., Uses victim's MAPI-standard e-mail address specific date, absence of employee record) book Time bombs (set off on a date or category of Sends copies of itself to first 50 people on list date) are a subset of logic bombs E-mail message w/ subject line "Important Cross-site scripting malware Message From <name>” Exploit flaws in Web application servers & client Spread faster than any previous virus code Followed by similar e-mail-enabled viruses In 2005, “Samy” created script that generated >1M “friends” on MySpace using flaw in Internet Explorer to use JavaScript insertion exploit Sentenced to 3 years probation, 90 days 19 Copyright © 2014 M. E. Kabay. All rights reserved. 20 community Copyrightservice © 2014 M. E. Kabay. All rights reserved. Viruses (5) Viruses vs Worms Polymorphic viruses Viruses integrate into host code Intended to defeat signature- Replicate upon execution of infected code based antivirus tools Worms are free-standing code Modify themselves at time of Replicate via networks replication Polymorphic Engine E-mail (e.g., Outlook) especially common vector Encrypts code Some worms have viral properties Includes self-decryption capability Integrate themselves into e-mail Dark Avenger wrote MtE (aka messages and convert them to Mutation Engine) in late 1980s executable files Programmer from Sofia, Bulgaria Frequently conceal executable file type Detested Vesselin Bontchev, famous AV expert Depend on default suppression of file Also attacked researcher Sarah Gordon by suffix (e.g., AnnaKournikova.jpg.vbs.txt) name 21 Copyright © 2014 M. E. Kabay. All rights reserved. 22 Copyright © 2014 M. E. Kabay. All rights reserved. 1987: IBM Christmas Tree Worm 1988: The Morris Worm E-mail sent via IBM internal e-mail network Robert T. Morris (not a “Robert T. Morris, Jr”!) Included program to draw ASCII Christmas tree on screen Cornell University grad student Son of famed NSA cryptographer Used recipient’s e-mail address book to Robert H. Morris mail itself to everyone on the network Wrote paper on sendmail and fingerd No mechanism to prevent vulnerabilities on UNIX systems superinfection Seems to have intended to Overloaded worldwide IBM networks demonstrate significance Messages escaped from IBM into Released a defective version of his demo worm BITNET Originally intended to replicate slowly, avoid superinfection In fact grew fast and superinfected systems worldwide 23 Copyright © 2014 M. E. Kabay. All rights reserved. 24 Copyright © 2014 M. E. Kabay. All rights reserved. 1999-12 W.95.Babylonia Morris Worm (cont’d) Virus/Worm Launched Worm at 17:00 on 2 November 1988 Extensible virus By 06:00 next morning the Internet was effectively Payload modified remotely down Trojan virus-dropper ~6,000-9,000 systems crashed or taken offline Disguised as Y2K bug fix for internet relay Computer scientists worked feverishly all night chat (IRC) users analyzing the Worm Sent itself other users Distributed fixes by telephone and fax (no ‘Net) Polled Internet site in Japan Led to formation of CERT-CC® in Dec 1988 Looked for updated plugins Morris convicted of violating 1986 Computer Fraud and Abuse Act (18 USC §1030) 400 hours community service + $10K fine 25 Copyright © 2014 M. E. Kabay. All rights reserved. 26 Copyright © 2014 M. E. Kabay. All rights reserved. 2000-05: ILOVEYOU 2000-06: Timofonica Worm Worm E-mail subject ILOVEYOU E-mail attachment E-mail enabled malware LOVE-LETTER-FOR-YOU.TEXT.vbs Automatically sent pager Used all addresses in address book message to block of Telefonica cell phones Became #1 infectious code in Europe, Asia, USA Tried to delete all data on Variants appeared quickly hard disk Created by 27-yr-old Filipino computer student Onel de Guzman No local laws against spreading viruses Creator given job as programmer! 27 Copyright © 2014 M. E. Kabay. All rights reserved. 28 Copyright © 2014 M. E. Kabay. All rights reserved. 2001-03: SirCam Worm 2001-06: CodeRed Worm Propagated on Windows systems Infected vulnerable Web servers Used standard e-mail address books Windows NT or Windows 2000 or CISCO equipment running MS-IIS software that has