Rank 1

S&P (Oakland)

IEEE Symposium on Security and Privacy

CCS

ACM Conference on Computer and Communications Security

Crypto 

International Cryptology Conference

Eurocrypt

European Cryptology Conference

Security

Usenix Security Symposium

NDSS

ISOC Network and Distributed System Security Symposium

Rank 2

ESORICS 

European Symposium on Research in Computer Security

RAID

International Symposium on Recent Advances in Intrusion Detection

ACSAC

Annual Computer Security Applications Conference

DSN

The International Conference on Dependable Systems and Networks

CSF (CSFW)

IEEE Computer Security Foundations Symposium.
Supersedes CSFW (Computer Security Foundations Workshop)

TCC

Theory of Cryptography Conference

Asiacrypt

International Conference on the Theory and Application of Cryptology and Information Security

IMC

Internet Measurement Conference

Rank 3

SecureComm 

IEEE Communications Society/CreateNet Internation Conference on Security and Privacy for Emerging Areas in Communication Networks

DIMVA

GI SIG SIDAR Conference on Detection of Intrusions and Malware and Vulnerability Assessment

AsiaCCS

ACM Symposium on Information, Computer and Communications Security

ACNS

International Conference on Applied Cryptography and Network Security

FC

International Conference on Financial Cryptography and Data Security

SAC

ACM Symposium on Applied Computing

ACISP

Australasia Conference on Information Security and Privacy

ICICS

International Conference on Information and Communications Security

ISC

Information Security Conference

ICISC

International Conference on Information Security and Cryptology

SACMAT

ACM Symposium on Access Control Models and Technologies

CT-RSA

RSA Conference, Cryptographers' Track

SEC

IFIP International Information Security Conference

WiSec
(WiSe, SASN)

ACM Conference on Wireless Network Security
Supersedes WiSe (ACM Workshop on Wireless Security) and SASN (ACM Workshop on Security of Ad-Hoc and Sensor Networks)

SOUPS

Symposium On Usable Privacy and Security

IFIP WG 11.9

IFIP WG 11.9 International Conference on Digital Forensics

-- Workshops below --

DFRWS

Digital Forensic Research Workshop

FSE

Fast Software Encryption workshop

PKC

International Workshop on Public-Key Cryptography

NSPW

New Security Paradigms Workshop

IH

Workshop on Information Hiding

WSPEC

Workshop on Security and Privacy in E-commerce

DRM

ACM Workshop on Digital Rights Management

IWIA

IEEE International Information Assurance Workshop

IAW

IEEE SMC Information Assurance Workshop "The West Point Workshop"

CHES

Workshop on Cryptographic Hardware and Embedded Systems

SRUTI

USENIX Workshop on Steps to Reducing Unwanted Traffic on the Internet

HotSec

USENIX Workshop on Hot Topics in Security

LEET
(HotBots,WORM)

USENIX Workshop on Large-scale Exploits and Emergent Threats
Supersedes HotBots (USENIX Workshop on Hot Topics in Understanding Botnets) and WORM (ACM Workshop on Recurring/Rapid Malcode)

Others (not ranked)　

ISPEC

Information Security Practice and Experience Conference