Passwords Everywhere GOPAS: | | Ing. Ondřej Ševeček | GOPAS a.s. | MCM: Directory Services | MVP: Enterprise Security | Certified Ethical Hacker | | |

Take care of your passwords  People use the same passwords for different services AD network, mobile phone, credit card PIN, facebook, e- shops, fre , …  People type their passwords on unknown computers  Passwords travel over network unencrypted  Somebody else is your computer administrator  Computers store passwords often in full form

Hardware keyloggers  Easy soldier

Different service = different password?  Do you thing the databases of facebook, google+, gmail, microsoft, alza, seznam, … are encrypted? nonsense  What do you thing the Indians do when bored? are they surfing your , or facebook?  What do you thing is the first thing a virus is going to do after infection? list all user accounts touch anything in your network with your current password

User Account Control (UAC)  Locally limits Administrators group membership  Does nothing over network  It matters only for a BFU on a single machine  It does not affect administrative accounts

Windows authentication seems secure  Kerberos, Kerberos, Kerberos, sometimes NTLM  Encrypted network transport AES, mutual authentication, rekeying, etc.

Passwords are in memory Internet Explorer Outlook Lync Ctrl-Alt-Del LSASS IS Client plaintext password

Server Passwords are in LSASS memory Internet Explorer Outlook Lync Local LSASS Server LSASS Kerberos NTLM IS Client plaintext password

Who can steal passwords from LSASS  Local Administrators Debug privilege is just the only necessary to break into LSASS memory

Basic authentication  HTTP Basic authentication used veeeeery often even on intranets mostly BFU accounts  LDAP Simple bind used veeeeery often by third-party NAS, VPN, VoIP, gateways, routers, VMWare console, etc. often administrative accounts  RDP used extreeeeemely often extreeeeemely often administrative accounts

Server Passwords are in LSASS memory Internet Explorer Outlook Lync Server LSASS plain-text IS Client MSTSC plaintext password VPN

Passwords are stored in full form  IIS application pools  Services  Scheduled tasks

After attack, change your password!  Really?  Password filter on DC or on local SAM database

Good password  Long at least 12 characters  All four types of characters (a-z, A-Z, 0-9, #$%^…) 80% passwords are alfa-numeric  Never reuse the same password for critical services not too much change necessary

Password locking?  Do not exagerate 6 characters complex password 75 trials per one lock for 1 minute = years

Cracking from local/AD hashes (non-cache)  MD4 hashes brute-force 8 characters complex  1 CPU = 25 years  10 GPUs = 15 days rainbow-table 8 characters complex  = minutes  = 120 GB  Every character makes it 80x more difficult  12 characters complex password is unbreakable at least for non-NSA mortals

Cracking from network trace and password cache  No use for rainbow-table MD4 salted  Only brute-force possible

What to remember  Never type a password on an unknown computer  Accessing remote machines with RDP sends there your password  Disable all HTTP Basic and LDAP Simple bind authentications  Use smart cards instead

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NASHLEDANOU GOPAS: | | na kurzech v počítačové škole GOPAS, a.s. GOC171 - Active Directory Troubleshooting GOC172 - Kerberos Troubleshooting GOC173 - Enterprise PKI Deployment GOC175 - Administering Security