security plus


Security+ is a vendor-neutral certification that validates the baseline skills and knowledge required to perform core security functions and pursue an IT security career. The Security+ exam covers a broad range of topics including security administration, threats and vulnerabilities, access control, cryptography, and organizational security.

1: Introduction to Security

CIA : Confidentiality, Integrity, Availability

- Confidentiality : Prevents disclosure of information to outside party
- Integrity : Guarantees data has not been tampered with
- Availability : Resources can be accessed when needed

AAA : Authentication, Authorization, Accounting(non-repudiation)

- Authentication : Confirms one’s identity e.g.) username/password, biometrics, signature etc
- Authorization : Allows one to access certain materials e.g.) ACL(Access Control Lists), Linux permission bits etc
- Accounting : Tracking of data/comp./netwrk resources usage for individualse.g.) Logging, auditing, data/network monitoring

Types of Threats

- Malicious Software
- Unauthorized Access
- System Failure
- Social Engineering

Physical, Technical, Administrative Security plans

- Physical : Physical security systems such as alarms, ID cards, CCTV etc
- Technical : Smart cards, ACLs, encryption etc
- Administrative : Policies, procedures, DRP(Disaster recovery plan) etc

Protection Methods

- User Awareness
- Authentication
- Anti-malware
- Data Backups
- Encryption
- Data Removal

*Good security plan + Good protection method = Solid defense (Defense in depth)

Types of Hackers

- White Hat
- Black Hat
- Grey Hat
- Blue Hat (Bounty Hunters)
- Elites (Zero day discoverers)

Types of Attackers

- Script Kiddie
- Hacktivist
- Organized Crime
- APT(Advanced Persistent Threat aka Nation state attacker)

2 : Computer Systems Security Part 1 (Malware)

Types of Malware

- Viruses
	Malicious code executed by the user, lives on a file
	> Boot Sector : Placed in first hard drive sector
	> Macro : Placed into documents
	> Program : Infects executables
	> Encrypted : Avoids detection through encryption
	> Polymorphic : Decryption module changes with every infection
	> Metamorphic : Whole virus code changes with every infection
	> Stealth
	> Armored : Misdirects antivirus away from its actual location
	> Multipartite : Hybrid of boot sector and program
- Worms
Malicious code that replicates, standalone program, may spread automatically
- Trojans
	Appear to be beneficial but contain malicious code
	> Keygens
	> RAT Trojans
- Ransomware
	Encrypts files and data and demands payment to unlock
	Often propagates as a Trojan or a worm
- Spyware
	Usually hidden inside third party applications
	Logs various user activities and sends it to attacker
	Also associated with Adware and Grayware
- Rootkits
	Designed to gain administrative control over a machine
	Hard to detect b/c it targets low level(UEFI/BIOS, kernel etc)
	Activates before Antivirus/OS
- Spam
	Abuse of electronic messaging system

Malware Delivery

Treat Vector vs Attack Vector
- Software, Messaging and Media
	> Emails, FTP, P2P/torrent file downloads
	> Removable Media
- Typosquatting
- Exploit kit
- Botnets and Zombies
	> Also used for DDOS or financial gain
- Active Interception (MITM)
- Privilege Escalation
- Backdoor
	> Authentication bypass mechanisms built into the program itself
- Logic Bombs
	> Triggers malware on certain condition(date, OS type etc)

Malware Prevention / Troubleshooting Common Symptoms : Slow computer speed, crashes, incorrect home page, popups Common Prevention > Antivirus : Regular updates and scans Detects : worms, viruses and Trojans Does not detect : Botnet activity, rootkits, logic bombs > Firewalls and Regular OS updates > Separation of OS and data > Hardware + Software based firewall (e.g. router + Windows Firewall) > Encryption for confidentiality (Windows EFS) Common Steps to Malware Removal 1. Identify Symptoms 2. Quarantine infected system / drive to clean machine 3. Disable System Restore 4. Remediate affected system > Update AV / Scan and removal 5. Schedule scans and run update 6. Enable system restore and set new restore point 7. Educate end user Worms and Trojans > Antivirus, Regular maintenance and vigilance Spyware > Antivirus, browser security settings, remove unnecessary application > End user education Rootkits > Antivirus, Rootkit detectors (USB bootable OS) > Use UEFI over BIOS (GPT over MBR) > Wipe the entire drive & reinstall OS Spam > Spam filter, whitelisting/blacklisting, close open mail relays

3 : Computer Systems Security Part 2

Security Applications

- Personal Firewalls (Host based firewalls)
	> Windows Firewall
	> ZoneAlarm
	> Packet Filter and IP Firewall (Mac OSX)
	> iptables (Linux)
- IDS (Intrusion Detection System)
	Host Based : Loaded onto individual machine
			 Analyzes and monitors that one machine state
			 Can interpret encrypted traffic
	Network Based : Either loaded onto a machine or standalone device
			    Monitors every packet going through network interface
			    Monitors multiple devices, less expensive
			    Cannot monitor what happens in an OS
- Monitoring Types –
Statistical Anomaly vs Signature
		> Statistical Anomaly Establishes baseline and compares current performance
		> Signature
			Network traffic analyzed to find predetermined patterns
	HIDS examples
		> Trend Micro OSSEC (freeware)
		> Verisys (Commercial, Windows)
		> Tripwire (Commercial)
	* Make sure to protect HIDS database with encryption and access control
- Popup Blockers
	Ad filtering & Content filtering
- DLP (Data Loss Prevention)
	Monitors data in use / in motion / at rest
	Prevents unauthorized use and leakage of data
	Types of DLP
		> Endpoint DLP : Runs on single machine, software based
		> Network DLP : Software/hardware, installed on network perimeter
		> Storage DLP : Installed in data centers/server rooms

Securing Computer Hardware and Peripherals Examples of peripherals: USB flash drives, SATA external HDD, optical disks Securing BIOS - Flashing (Updating) BIOS firmware - BIOS password - Configure BIOS Boot order - Secure boot (disables unsigned device drivers, UEFI) * UEFI and Root of Trust, secure/measured boot, attestation Securing Storage Devices - Removable Storage > Typically prohibits all removable storage besides specific ones > Removable Media Controls USB Lockdown (BIOS), limit USB use, malware scans, audits - NAS (Network Attached Storage) > Built for high availability (no downtime) > Commonly implemented as RAID array (levels depend on situation) > Use encryption, authentication, secure logging etc - Whole Disk Encryption > Requires either self encrypting or full disk encryption SW > Windows BitLocker requirements 1) TPM or External USB key with encrypted keys 2) Hard drive with 2 volumes(1 for boot, 1 to be encrypted) > Double Encryption – BitLocker + EFS - HSM (Hardware Security Modules) Vs TPM TPM handles key storage with limited cryptographic function HSM handles mainly quick crypto functions with key storage Found in USB attachment or network attached device

Securing Wireless Peripherals - Force devices to use AES or WPA2 encryption for data transmission

Securing Mobile Devices General Security - Keep phone number secure and do not respond to unsolicited calls - Update mobile device OS - Complex password and limit downloads to device Malware - Install & update mobile device AV - Take use of built in security features - Avoid following links, don’t store information on device - Don’t post info on social media Botnet Activity - Follow anti-malware procedures - Avoid rooting / jailbreaking phones SIM Cloning - A cloned SIM redirects all calls and texts to its own device - Able to hijack messages intended for original SIM card owner Wireless Attacks - Bluejacking - Bluesnarfing

	- Full device encryption(FDE)
	- Set up GPS tracking
	- Remote lock & Remote wipe technology
Mobile Application
	- Mobile key management : use Third party software (Verisign)
	- Application whitelisting / blacklisting
	- Strong SMS application and endpoint security
	- Mobile payment : avoid public networks, user education
	- Geotagging : Disable GPS depending on situation
	- BYOD concerns
		> Storage Segmentation : divide corporate vs private data storage
		> Mobile Device Management systems for corporations