Sites:
SecurityFocus
http://www.securityfocus.com/

FrSIRT
http://www.frsirt.com/english/

GovernmentSecurity
http://www.governmentsecurity.org/

SecuriTeam
http://www.securiteam.com/

CERT
http://www.cert.org/

packet storm
http://packetstormsecurity.org/

milw0rm
http://www.milw0rm.com/

NewOrder
http://neworder.box.sk/

Insecure
http://www.insecure.org/

Security Stats
http://www.securitystats.com/

SecurityForest
http://www.securityforest.com


Magazines:

2600: The Hacker Quarterly
http://www.2600.com/

Phrack
http://www.phrack.org

Blacklisted 411
http://blacklisted411.net/

Hakin9
http://en.hakin9.org/

Hack-Tic
http://www.hacktic.nl/

C=Hacking
http://www.ffd2.com/fridge/chacking/


Cryptography:

Handbook of Applied Cryptography -
http://www.cacr.math.uwaterloo.ca/hac/

Cracking DES: Secrets of Encryption Research -
http://www.mirrors.wiretapped.net/se...crack-1-4.html



Enjoy!