40 Years of Internet Arms Races… Bill Cheswick ches@lumeta. com http: //www. lumeta. com 81 slides
Thinking about security… 81 slides
Talk outline • Intro • Some thoughts on thinking bad thoughts • Various races • Predictions – You got that with the 40 years, right? • Wishes – My dad’s computer, and Windows OK – Windows SP 2 40 Years of Internet Arms Races 3 of 81
Since some of you asked… • Chief Scientist at Lumeta, a Bell Labs spinoff – Founded in 2000. 45 people in the company • We map large corporate and government networks, and find leaks in the network perimeter • I am still figuring out what a chief scientist does • Second edition of the firewalls book came out last year: Cheswick, Bellovin, Rubin 40 Years of Internet Arms Races 4 of 81
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Before the whining and predicting, something useful • Lost friends web page • Cheap research web pages • Please give me feedback if I get something wrong – I do get out much from my little Internet startup (Lumeta) – You folks keep me honest. 40 Years of Internet Arms Races 6 of 81
Security People are Paid to Think Bad Thoughts -Bob Morris 81 slides
Fred Cohen and me 81 slides
What do you do with bad thoughts? • The world is full of threats • One can get a bit pessimistic • CIA asked a number of us for some of our bad thoughts • Watch your ethics! Are you battling the forces of darkness? 40 Years of Internet Arms Races 9 of 81
Questions about an evil idea • Has it already been done? How would you detect it? • If not, why hasn’t it happened yet? • What are the strategic preparations needed? • What are the tactical preparations needed just before the attack? • Can we detect strategic preparations? • Can we detect tactical preparations? 40 Years of Internet Arms Races 10 of 81
Minor example: Internet mapping 40 Years of Internet Arms Races 11 of 81
Minor example: Internet Mapping Project • Hal Burch and me, since 1998 • AUCERT has corresponded (complained) to us a number of times • Basic technology: 250, 000 traceroutes/day • Question: who else is doing this? 40 Years of Internet Arms Races 12 of 81
10: 45: 42 11: 28: 12 10: 57: 05 11: 30: 59 udp udp udp 5 uma 1. co. umatilla. or. us 1 64. d 9 b 7 d 1. client. atlantech. net 43101: 24@0+ omval. tednet. nl 43101: 1456@24+ omval. tednet. nl 43101: 625@1480 omval. tednet. nl 7 ns 1. yamato. ibm. com 40 Years of Internet Arms Races 13 of 81
Minor example: Internet Mapping Project • Andrew Gross and rstatd 40 Years of Internet Arms Races 14 of 81
Some thoughts on computing safety • Morris worm at Bell Labs (1988) • “Best block is not be there” – Karate Kid I • “You got to get out of the game” – Fred Grampp • I’ve never detected a virus or worm on one of my important systems. 40 Years of Internet Arms Races 15 of 81
Don’t let opposition practice on you during an arms race • Dictionary attacks on passwords • Crashme tests on programs, protocols, and operating systems – Weakness using COTS! 40 Years of Internet Arms Races 16 of 81
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The Internet security arms race • Defenders can control the battlefield • An uneasy truce may be good enough, if the business case can make usable predictions 40 Years of Internet Arms Races 18 of 81
The Internet is a fine place to practice attacks • Automated • Anonymous • Many “volunteers” • Don’t give them a dictionary, “oracle”, or “cribs” to try automated attacks on • Monoculture of software in hosts and routers 40 Years of Internet Arms Races 19 of 81
The Internet is a fine place to practice defenses • MILnet has been under attack since the mid 1980 s • That makes the threats much clearer • It gives the defenders a chance to get good at their job 40 Years of Internet Arms Races 20 of 81
Arms Races: Eavesdropping 81 slides
Arms race: Eavesdropping • Ethernet, ftp, and telnet were poor starts • WEP, POP 3, IMAP, AIM added to the confusion – POP 3 passwords are the most common I sniff over the air at conferences like this • Crypto wars of the mid-1990 s tied our hands • This race should be over, victory to the defenders 40 Years of Internet Arms Races 22 of 81
Eavesdropping victories • SSL ends direct credit card sniffing • Ssh lets me access secure machines from anywhere • IP/SEC is a bit of a pain to deploy, but that should get better – VPN products are very useful • CPUs have plenty of spare power now. • Check your work with dsniff 40 Years of Internet Arms Races 23 of 81
Eavesdropping problems • Casual web access and DNS queries still mostly in the clear. • Most ISPs still offer or insist on POP 3 and IMAP, not SSL versions of these • Widespread use of client certificates could limit access to these possibly dangerous network services 40 Years of Internet Arms Races 24 of 81
Eavesdropping arms races • Attack patterns vs. snort • Tcpdump/libpcap vs. killer packets 40 Years of Internet Arms Races 25 of 81
Arms Race: Battle for control of the computer and data 81 slides
The battle for control of the computer • Who owns the software in your computer? Who should be allowed to add and run programs? – Microsoft has assumed this since DOS • Viruses and worms • Pop-overs and pop-unders • Spyware • Automatic update systems • Same battle over data in computers controlling your car – Thermostat? Front door lock? Toaster? 40 Years of Internet Arms Races 27 of 81
Goals for this extraware • Zombie nets to assist with malfeasance, including forwarding of spam • Collect marketing data • Display advertisements • Enforce licensing restrictions 40 Years of Internet Arms Races 28 of 81
Solution: operating system only executes known programs • Virus problem goes away • Unix/Linux systems mostly do this already • OS updates and auxiliary program installs a problem • This feature not available on Microsoft operating systems (see below) 40 Years of Internet Arms Races 29 of 81
Extraware problems • Some business practices assume this ability is available • Some web page writers assume that I am willing to use possibly dangerous features in my browser (or a particular browser) 40 Years of Internet Arms Races 30 of 81
Virus arms race • Early on, detectors used viral signatures • Virus encryption and recompilation (!) has thwarted this • Virus detectors now simulate the code, looking for signature actions • Virus writers now detect emulation and behave differently • Virus emulators are slowing down, even with Moore’s Law. 40 Years of Internet Arms Races 31 of 81
Virus arms race • I suspect that virus writers are going to win the detection battle, if they haven’t already – Emulation may become too slow – Even though we have the home-field advantage – Will we know if an undetectable virus is released? • Best defense is to get out of the game. – Don’t run portable programs, or – Improve our sandbox technology • People who really care about this worry about Ken Thompson’s attack – Read and understand “On Trusting Trust” 40 Years of Internet Arms Races 32 of 81
The emulation arms race • Vmware versus the real thing – 4 tphi • Honeypots vs. bulkers – http: //www. sendsafe. com/honeypothunter. php 40 Years of Internet Arms Races 33 of 81
Arms Race: Authentication and identification 81 slides
Password cracking • Works 3% to 60% of the time using offline dictionary attacks – More, if the hashing is misdesigned • This will never get better, so… • We have to get out of the game 40 Years of Internet Arms Races 35 of 81
Passwords sniffed at this conference 40 Years of Internet Arms Races 36 of 81
Authentication/Identification Arms races • Password/PIN selection vs. cracking • Human-chosen passwords and PINs can be ok if guessing is limited, and obvious choices are suppressed • Password cracking is getting better, thanks to Moore’s Law and perhaps even botnets 40 Years of Internet Arms Races 37 of 81
Tony Sale Colossus (ver 2. 0) 40 Years of Internet Arms Races 38 of 81
We don’t know how to leave the user in charge of security decisions, safely. 40 Years of Internet Arms Races 39 of 81
Authentication solutions: two factor authentication • In my laptop: ssh key unlocked by long passphrase • Better: USB “key” unlocked by PIN. Five bad PINS, and it is gone. – We already carry a bunch of keys, so why not one more 40 Years of Internet Arms Races 40 of 81
Hardware tokens • These need to be open source drivable, and cheap • The business model has never been one for global adoption • Challenge/response form factor is the safest, but not acceptable if humans are in the loop 40 Years of Internet Arms Races 41 of 81
Authentication arms race: predictions • We’ve already won this, from a business model standpoint – Web SSL plus password is good enough for banking • USA needs two factor authentication for social security number. (Something better than MMN or birth date. ) • I don’t see this improving much, but a global USB dongle would do it • Don’t wait for world-wide PKI. 40 Years of Internet Arms Races 42 of 81
Arms race (sort of): destructible hardware 81 slides
Arms race (sort of) hardware destruction • IBM monochrome monitor • Some more recent monitors – Current ones? • Hard drives? Beat the heads up? • EEPROM write limits – Viral attack on. cn and. kr PC motherboards – Other equipment • Anything that requires a hardware on-site service call 40 Years of Internet Arms Races 44 of 81
Arms race (sort of) hardware destruction • Rendering the firmware useless – This can be fixed (mostly) with a secure trusted computing base. 40 Years of Internet Arms Races 45 of 81
Software upgrade race: literally a race • Patches are analyzed to determine the weakness • Patch-to-exploit time is now down below 10 hours – NB: spammers have incentive to do this work • Now the good guys are trying to obfuscate code! • Future difficult to say: dark side obscures everything. 40 Years of Internet Arms Races 46 of 81
Arms Races: firewalls • IP blocking • Ip aware (stateful) – More dangerous – Permits firewalking • Ultimately, firewalls are a hack, and should go away 40 Years of Internet Arms Races 47 of 81
Arms Races: deception 81 slides
West coral Snake Scarlet king snake 40 Years of Internet Arms Races 49 of 81
(the west coral snake is venomous) 81 slides
Arms Races: deception • Jails – Cliff Stoll and SDInet • Honeypots – Honeynet – honeyd • The deception toolkit---Fred Cohen 40 Years of Internet Arms Races 51 of 81
Bulkers vs honeypots • http: //www. send- safe. com/honeypothunter. php 40 Years of Internet Arms Races 52 of 81
User education vs. user deception • We will continue losing this one • Even experts sometimes don’t understand the ramifications of choices they are offered 40 Years of Internet Arms Races 53 of 81
Historic Arms races • SYN packet attacks • TCP sequence number guessing 40 Years of Internet Arms Races 54 of 81
My Dad’s computer Skinny-dipping with Microsoft 81 slides
Case study: My Dad’s computer • Windows XP, plenty of horsepower, two screens • Applications: – Email (Outlook) – “Bridge: ” a fancy stock market monitoring system – AIM • Cable access, dynamic IP address, no NAT, no firewall, outdated virus software, no spyware checker 40 Years of Internet Arms Races 56 of 81
This computer was a software toxic waste dump • It was burning a liter of oil every 500 km • The popups seemed darned distracting to me • But he thought it was fine – Got his work done – Didn’t want a system administrator to break his user interface somehow 40 Years of Internet Arms Races 57 of 81
A proposal: Windows OK 81 slides
Windows OK • Thin client implemented with Windows • It would be fine for maybe half the Windows users – Students, consumers, many corporate and government users • It would be reasonable to skinny dip with this client – Without firewall or virus checking software 40 Years of Internet Arms Races 59 of 81
Windows OK • No network listeners – None of those services are needed, except admin access for centrally-administered hosts • Default security settings • All security controls in one or two places • Security settings can be locked 40 Years of Internet Arms Races 60 of 81
Windows OK (cont) • There should be nothing you can click on, in email or a web page, that can hurt your computer – No portable programs are executed ever, except… • Active. X from approved parties – MSFT and one or two others. List is lockable 40 Years of Internet Arms Races 61 of 81
Windows OK • Reduce privileges in servers and all programs • Sandbox programs – Belt and suspenders 40 Years of Internet Arms Races 62 of 81
Office OK • No macros in Word or Power. Point. No executable code in Power. Point files • The only macros allowed in Excel perform arithmetic. They cannot create files, etc. 40 Years of Internet Arms Races 63 of 81
Vulnerabilities in OK • Buffer overflows in processing of data (not from the network) • Stop adding new features and focus on bug fixes • Programmers can clean up bugs, if they don’t have a moving target – It converges, to some extent 40 Years of Internet Arms Races 64 of 81
Microsoft client security It has been getting worse: can they skinny-dip safely? 81 slides
Windows ME Active Connections - Win ME Proto TCP UDP UDP UDP Local Address 127. 0. 0. 1: 1032 223. 10: 139 0. 0: 1025 0. 0: 1026 0. 0: 31337 0. 0: 162 223. 10: 137 223. 10: 138 Foreign Address 0. 0: 0 *: * *: * 40 Years of Internet Arms Races State LISTENING 66 of 81
Windows 2000 Proto TCP TCP TCP UDP UDP Local Address 0. 0: 135 0. 0: 445 0. 0: 1029 0. 0: 1036 0. 0: 1078 0. 0: 1080 0. 0: 1086 0. 0: 6515 127. 0. 0. 1: 139 0. 0: 445 0. 0: 1038 0. 0: 6514 0. 0: 6515 127. 0. 0. 1: 1108 223. 96: 500 223. 96: 4500 Foreign Address 0. 0: 0 0. 0: 0 *: * *: * 40 Years of Internet Arms Races State LISTENING LISTENING LISTENING 67 of 81
Windows XP, this laptop Proto TCP TCP TCP TCP UDP UDP UDP UDP Local Address ches-pc: epmap ches-pc: microsoft-ds ches-pc: 1025 ches-pc: 1036 ches-pc: 3115 ches-pc: 3118 ches-pc: 3470 ches-pc: 3477 ches-pc: 5000 ches-pc: 6515 ches-pc: netbios-ssn ches-pc: 3001 ches-pc: 3002 ches-pc: 3003 ches-pc: 5180 ches-pc: microsoft-ds ches-pc: isakmp ches-pc: 1027 ches-pc: 3008 ches-pc: 3473 ches-pc: 6514 ches-pc: 6515 ches-pc: netbios-ns ches-pc: netbios-dgm ches-pc: 1900 ches-pc: ntp ches-pc: 1900 ches-pc: 3471 Foreign Address ches-pc: 0 ches-pc: 0 ches-pc: 0 ches-pc: 0 *: * *: * *: * *: * State LISTENING LISTENING LISTENING LISTENING 40 Years of Internet Arms Races 68 of 81
Free. BSD partition, this laptop Active Internet connections (including servers) Proto Recv-Q Send-Q Local Address Foreign Address tcp 4 0 0 *. 22 *. * tcp 6 0 0 *. 22 *. * 40 Years of Internet Arms Races 69 of 81
XP SP 2 Bill Gets It 81 slides
Microsoft’s Augean Stables: a task for Hercules • 3000 oxen, 30 years, that’s roughly one oxen -day per line of code in Windows • It’s been getting worse since Windows 95 40 Years of Internet Arms Races 71 of 81
XP SP 2: Bill gets it • “a feature you don’t use should not be a security problem for you. ” • “Security by design” – Too late for that, its all retrofitting now • “Security by default” – No network services on by default • Security control panel – Many things missing from it – Speaker could not find Active. X security settings • There a lot of details that remain to be seen. 40 Years of Internet Arms Races 72 of 81
Microsoft really means it about improving their security • Their security commitment appears to be real • It is a huge job • Opposing forces are unclear to me • It’s been a long time coming, and frustrating 40 Years of Internet Arms Races 73 of 81
Microsoft secure client arms race • We are likely to win, but it is going to be a while 40 Years of Internet Arms Races 74 of 81
Ches’s wish list • browsersandbox. org – Uses a. conf file, supplied with browser – Same. conf file for any major OS – Sandbox is impenetrable, no matter what • I know people have offered solutions for ten years • I need portability: Linux, Free. BSD, maybe even MSFT, which needs sand boxing in their OS. 40 Years of Internet Arms Races 75 of 81
Ches’s wish list (cont. ) • Self-jailing samba • Self-jailing apache 40 Years of Internet Arms Races 76 of 81
Ches’s wish list (cont. ) • USB “key” for every computer • No big investment for centralized servers • Open source interface • Business model: the dongle hardware, not the servers and software – Atalla had this in 1988! • Different key for system administrator • Software that doesn’t abuse admin permission – I. e. least privilege 40 Years of Internet Arms Races 77 of 81
Conclusions • Computers are still like my Olds ’ 88 • They ought to stay that way, to foster creativity and alternatives • I think we will be getting better, over all 40 Years of Internet Arms Races 78 of 81
40 Years of Internet Arms Races Bill Cheswick ches@lumeta. com http: //www. lumeta. com 81 slides
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