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Ing. Ondřej Ševeček | GOPAS a.s. | MCM: Directory Services | MVP: Enterprise Security | ondrej@ sevecek.com | www.sevecek.com |. Secure Office. Motto. Thou shalt never assume The Rogue Warrior's Eight Commandment of SpecWar Richard Marcinko US Navy Seal.
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Ing. Ondřej Ševeček | GOPAS a.s. | MCM: Directory Services | MVP: Enterprise Security | ondrej@sevecek.com | www.sevecek.com | Secure Office
Motto • Thou shalt never assume The Rogue Warrior's Eight Commandment of SpecWar Richard Marcinko US Navy Seal
Attackers • External • don’t know anything about your environment • can try brute force passwords at most • vulnerability scanning • Internal • most severe threats • know their environment • have already at least some level of access • can steal data they are authorized to read
Protection: External Attackers • Firewalls • Antispam/Antimalware • Software Updates • Account Lockout
Current Internal Threats • Assuming • Physical security • computers • data • Passwords • cracking, keyloggers • Eavesdropping • wired/wireless networks • Spam/malware • directed attacks • Remote Access • from unsecure computers • Data theft by authorized readers • currently one of the most underestimated problem
Current Threats Assumptions
Vulnerabilities • Examples: • My wife crossing a road • PKI misconfiguration in a bank • Hidden accounts after virus attack • Malicious mail from home vs. from work
Protection: Assumptions • Never assume anything • Be careful • Know your enemy • Don’t do anything you don’t understand
Current Threats to a Secure Office Case Study
Environment • Windows 2008 R2 Datacenter • Windows 7 Enterprise • Exchange 2010 • SharePoint 2010 • Hyper-V • Office 2010 • mobile devices with ActiveSync
Current Threats to a Secure Office Physical Security
Vulnerabilities • Computers easily accessed by a lot of people • employees • maintenance staff • theft from branch offices • Attacks • stealing the whole machine • stealing the data only • Physical access = local administrator
Machines and Network • Servers • rack security • Data storage • Client computers • desktops, notebooks • usually caching data • Peripherals • Remote offices • Wireless and wired networks • AirPCap, USB ethernet switch/netbook
Protection: Physical access • Limit physical access • Place computers/storage into secure locations • +hardware locks, cables • Use notebooks instead of desktops • Use remote desktop/terminal • Encryption
Protection: BitLocker • Disk partition encryption • AES • Provide password on startup • prevents others from becoming an administrator • Use TPM • prevents owner from becoming an administrator • Trusted Platform Module • stores the password on motherboard • checks signatures of BIOS, CMOS, MBR, Boot Sector, loader etc.
Protection: BitLocker • Recovery keys in Active Directory • Windows 7 Enterprise • Gemalto .NET smart-cards • workstations/ntb require S/C to boot • manually enrolled • combined with user logon certificates
Protection: 802.1x • Network Access • Ethernet, WiFi • EAP-TLS • Certificate authentication • computer/user • computer + user • automatic enrollment, AD computer account
Protection: 802.1x PC PC PC PC Managed Switch PC Switch ManagedSwitch PC PC Printer PC
Current Threats to a Secure Office Network Communications and Eavesdropping
Vulnerabilities • Free network access • No network traffic encryption • People ignore warnings • ARP poisoning
Protection: Firewall • Windows Firewall • IP/TCP/UDP/ICMP/AH/ESP inspection • FTP/PPTP/IPSec pass-through • IP/process filters • Network Location Awareness • Blocking client / client traffic
Protection: Eavesdropping • IPSec encryption • IP filters • Network Location Awareness • internal traffic only • Computer certificate authentication • automatically enrolled for AC machine account • AES, SHA-2
Protection: SSL Inspection • Threat Management Gateway • secure remote access • monitor users when “uploading” • Reverse inspection • Exchange, SharePoint, Terminal access • Forward • Antimalware, URL, classification
SSL Publishing Certificate 443 LAN Internet TMG Certificate 443 Web Server
SSL Certificate prices • Verisign – 1999 • 300$ year • Thawte – 2003 • 150$ year • Go Daddy – 2005 • 30$ year • GlobalSign – 2006 • 250$ year • StartCom – 2009 • free
SSL Assurance • Email loopback confirmation • Requires just a valid email address • No assurance about the target identity
EV Certificate prices • Verisign – 1999 • 1500$ year • Thawte – 2003 • 600$ year • Go Daddy – 2005 • 100$ year • GlobalSign – 2006 • 900$ year • StartCom – 2009 • 50$ year
Forward SSL Inspection LAN Internet TMG Certificate 443 Certificate 443 Certificate 443 Certificate 443
SSL Inspection (MITM) False Certificate Certificate Public key Public key Client AttackerTMG WebServer Private key Private key
Protection: Intrusion Prevention • Threat Management Gateway • Intrusion Prevention System • External/Internal/DMZ only
Current Threats to a Secure Office Passwords
Vulnerabilities • Keyloggers • software • hardware • Cache / Local Storage • Cracking
Local Password Storage • Full-text passwords • IE autocomplete • password “lockers” • fingerprint readers • service/scheduled-tasks accounts • Password hashes • local user accounts • all domain accounts on Domain Controllers • password caches
Password Cracking • Windows MD4 Hashes • local storage • LAN network capture • PPTP VPN • Offline • Rainbow Tables • severe up to 7 characters (minutes)
Protection: Passwords • Use smart cards • convenient (3-5 characters PIN) • Gemalto .NET without installation • Require strong passwords • admin accounts • Procedures, policies and audit • Never type sensitive passwords on insecure computers • Training
Protection: Password Policies • For individual groups/users • Granular Password Policies • Windows 2008 Domain Functional Level and newer • Non-complex password example • login: Ondrej • password: #.LonDo-NN.sea-s0n58 • Complex password example • September2011
Current Threats to a Secure Office Spam/Malware
Spam threats • No real prevention against spam • Spam created anonymously • no traces/auditing • Directed attacks cannot be automatically recognized
Malware Threats • Virus must be first detected after infection! • Backdoors just download the real infection • does antimalware know what exactly it was? • Reinstallation of the whole password domain! • users tend to use same passwords for more services • Stability and performance