Main Flashcards
Prepending
Two seperate definitions
1. Making a message appear more trustworthy by adding text before the message. E.g adding [SAFE] to the subject of an email.
2. Url high hijacking technique where the attacker puts text at the beginning of their typosquatted URL https://pprofessormesser.com/
Pharming
Similar to phishing but attacking DNS in order to redirect to your malicious site in order to harvest credentals.
Pretexting
A fictitious scenario added to a conversation to make a request more believable. Used by attackers in social engineering.
Hoaxes
A threat that doesn’t actually exit.
e.g Email chain about fake cyber attack
Methods for identifying spam
- Allowed list, trusted senders
- SMTP standards checking, block emails that don’t meet RFC standards
- rDNS, reverse DNS, block email where sender’s domai doesn’t match IP address
- Tarpitting, intentionally slow down server conversation
- Recipient filtering, block all email not addressed to valid recipient email address
Credential harvesting
Grabbing all the credentials stored on a PC, phone, etc
Principles of Social Engineering
- Authority
- Intimidation
- Consesus / Social Proof
- Scarcity
- Urgency
- Familiarity / Liking
- Trust
Types of malware
- Virus
- Crypto-malware
- Ransomware
- Worms
- Trojan horse
- Rootkit
- Keylogger
- Adware/Spyware
- Botnet
Virus
Malware that can reproduct itself through file systems or network. Key difference between worms: Virus requires user input to spread, like opening a malicious file
Worms
Malware that self-replicates across a network with no user interaction
Crypto-malware
Newer generation of ransomware, pay the bad guys for your data back. This is what you think of when you think “ransomware”
Ransomware
Malware that attempts to extort money from the target. May or may not encrypt data
Trojan horse
Malware that pretends to be something else, e.g Rouge AV
Rootkit
Malware that modifies core system files, can be invisible to the operating system and traditonal AV
e.g Malicious kernel drivers
Rainbow tables
Optimized pre-built set of hashes
Salt
Random data added to password when hashing. Every user gets own random salt. Stops rainbow tables. Slow down brute force process. Same password will create different hashes depending on the salt.
Machine learning attacks
- Poison the training data
- Find ways to evade the AI. E.g Holes in an AI based IPS or IDS
Birthday attack
Find a collison through brute force. Generate multiple versions of plaintext to match hashes.
Downgrade attack
Attacker forces the system use a worse form of encryption if it is supported.
Replay attack
Gather network information with a tap ARP poisoning, malware, or protocol analyzer. Then resend the information collected to the server, maybe it will be accepted as valid.
SSRF
Server side request forgery. Attacker tells the web server to do something, and it does it. Caused by bad programming and not checking for who sent the request.
Shimming
Code that acts as an adapater for backwards compatibility. Often written by malware developers.
Metamohpric Malware
Refactors itself to make it appear different each time. Intelligently redesigns itself.
SSL Stripping / HTTP Downgrade
Attacker sits in middle of conversation between victim and server. Attacker essentially has all the encryption keys, so it can decrypt the HTTPs data, giving plaintext. Attacker reads everything, but the victim thinks he’s running HTTPS the entire time.
Bluejacking
Sending unsolicited messages to another device via bluetooth
Bluesnarfing
Access a bluetooth-enabled device and transfer data
e.g Contact list, calendar, email, pictures, video, etc
Cryptographic nonce
Arbitrary number that is used only once in a cryptograhic process. Usually a random or psuedo-random number or a counter. A salt is an example of a nonce.
Initalization Vector (IV)
Type of nonce. Used for randomizing an encryption scheme.
MAC Flooding
Filling up the MAC table on a switch, forcing ou tthe legitmate MAC addresses. The switch will begin to flood out on all interfaces, turning the switch into a hub. Attacker can then easily capture all network traffic.
DNS poisoning
Modify the DNS server, change it so that DNS lookups give the responses that the attacker desires. Can be used to highjack domains, get victims to go to your malicious site, DOS.
URL Highjacking Techniques
- Typosquatting / brandjacking, takes advantage of poor spelling
- Outright mispelling
- Typing error
- Different phrase in URL
- Different top-level domain, e.g .org instead of .com
Types of threat actors
- Insiders
- Nation states
- Hackitivst
- Script kiddies
- Hackers
- Shadow IT
- Organized crime
- Competitors
Broad categories of threat intelligence
- Open source
- Closed/proprietary
Threat intelligence sources
- Vulnerability databases
- Information-sharing centers
- Automated indicator sharing (AIS)
- Indicators of compromise (IOC)
- Predictive analysis
- Dark web intelligence
- File/code repos
- Threat maps
Automated Indicator sharing (AIS)
Enables real-time exchange of machine-readable cyber threat indicators through a server/client architecture for communications.
TTP
Tactics, techniques, procedures used by adversaries
Threat hunting
Find the attacker before they find you
Types of vulnerability scans
- Non-intrusive
- Intrusive
- Credentialed
- Non-credentialed
Syslog
Standard for message logging, needs a lot of disk space, used on central log collector integrated into the SIEM
SOAR
Security orchestration, automation, and response
- Orchestration - Connect many different tools together
- Automation - Handle security tasks automatically
- Response - Make changes immediately
Pentester’s process
- Recon / footprinting
- Inital exploitation
- Lateral movement
- Persistence
- Pivoting
Security teams
- Red team
- Blue
- Purple - Red and blue working together
- White - Refs
Baseline configuration
Established reference point for integrity measurement checks.
Data masking
Techniques used to obfuscate sensitive data
Data states
- At rest
- In transit - Over network
- In use - Ram
Tokenization
Replace sensitive data with non-sensitive placeholder
IRM
Information Rights Management.
Technology used to limit the scope of what users can do with data. e.g Preventing copy past, screenshotting, printing, etc
Site resilliency: Types of sites
- Hot - Exact replica
- Warm - Between hot and cold
- Cold - Electricity, building, not much else
DNS Sinkhole
DNS that hands out incorrect IP addresses
Types of cloud models
- IaaS Infrastructure as a service - Sometimes called hardware as a service
- PaaS Platform - Someone else handles the platform you handle development, no servers, no software, no maintenance team, no HVAC
- SaaS Software - On demand software, no local installation
- XaaS Anything - Broad description of all cloud models
0 octal
000
1 octal
001
2 octal
010
3 octal
011
4 octal
100
5 octal
101
6 octal
110
7 octal
111
Data governance
Processes used by an organization to manage, process, and protect data. Used to ensure availability, readability, integrity, and security of data. Also, used to comply with external laws and regulations.
HIPAA
Health insurance portability and accountability act. A data governance regulation. Mandates that organizations protect health information.
GLBA
Gramm-leach Bliley act. Data governance regulation that requires financial institutions to provide consumers with a privacy notice explaining what information they collect and how it is used.
SOX
Sarbanes-oxley act. Data governance regulation that requires that executives take individual responsibility for the accuracy of financial reports.
GDPR
General data protection regulation. Data governance regulation that mandates the protection of privacy data for individuals who live in the EU
Data retention policy
Specifies how long data is retained and sometimes specifies where it is stored.
Blank
TCP 21, 22
SSH Port
TCP 22
DNS Port
53 tcp for zone transfers
53 udp for name resolution queries
NTP Port
UDP 123
BGP
Border gateway protocol
Enables exchange of routing information between autonomous systems
TCP 179
IPSec port
Uses internet key exchange (IKE) over port 500 UDP
RDP port
TCP 3389
POP3, secure POP ports
TCP 110 unencrypted
TCP 995 encrypted
Imap4 and encrypted imap ports
TCP 143 unencrypted
TCP 993 encrypted
Smtp and smtp-over-TLS port
TCP 25 unencrypted
TCP 587 for email encrypted with tls
Telnet port
TCP 23
FTP ports
Active mode: TCP 21 control signals, TCP 20 for data
Passive mode: TCP 21 control signals, random TCP port for data
Sftp
TCP 22
Secure FTP
Inherently secure. Unlike FTPS, which just adds a layer of security with TLS. Both are secure though.
Used by SSH for file transfers. Not FTPS!
LDAP, LDAPS
Lightweight Directory Access Protocol
LDAP TCP 389
LDAPS TCP 636
LDAP specifies the formats and methods used to query directories. Commonly is used to store information for authentication.
SSTP ports
Secure socket tunneling protocol
Encrypts VPN traffic using tls on port TCP 443
TFTP Port
Trivial file transfer protocol
UDP 69
Kerberos port
UDP 88
Ping
Ping -t 172.26.5.1, continuous
Ping -c 4 172.26.5.1, 4 times
Ipconfig
Ipconfig /all
Ipconfig /flushdns, flush dns cache
Ipconfig /displaydns, show dns cache
Ifconfig
Ifconfig -a, similar to ipconfig /all
Ifconfig eth0, show conf. eth0
Ifconfig eth0 promisc, enable promisc mode, process all traffic
Ifconfig eth0 allmulti, enable multicast mode, process all multicast traffic
Ifconfig eth0 -allmulti, disable multicase mode
Ip (tool)
Ip link show, show interfaces
Ip link set eth0 up, enable eth0
Ip -s link, show network stats
Netstat
Netstat -a, show all tcp udp ports being listened on
Netstat -r, show routing table
Netstat -e, show network stats
Netstat -s, show net stats for specific protocols
Netstat -n, show addresses and ports in numerical order
Netstat -p protocol, show stats on specific protocol
Netstat, show open TCP connections
You can combine options. E.g netstat -anp tcp
Tracert
Windows
tracert google.com, show hops between system and Google
racert -d google.com, don’t resolve IP addresses to host names, makes command faster
Traceroute
Linux
Traceroute -n google.com, don’t resolve IPs
Pathping
Sends pings to hops on routes. Computes statistics depending on responses to pings.
Pathping -n google.com
If a hop has 100% packet loss. Chances are it is just blocking icmp. If it really is bad, then all other hops from that point on in the path must also be dropping 100%.
Arp
Windows and Linux
Arp, help on windows, arp cache linux
Arp -a google.com, show arp cache entry for specified ip
Arp -a, show entire cache on windows
Tail
Tail -n 15 /var/log/messages, show last 15 lines.
Tail /var/log/messages, show last 10 lines
Logger
Linux
Add entires to /var/log/syslog
Journalctl
Linux
Query linux system logging utility called journald.
Journalctl – since “1 hour ago”, show logs only in journals.
Journalctl –list-boots, show boot logs
FAR
False acceptance rate
Biometrics
FRR
False rejection rate
Biometrics
CER
Crossover error rate
Point on graph of sensitivity (x), error percentage (y), where FAR and FRR intersect. Increasing or decreasing sensitivity at this point will cause one of the error rates to go up and the other to go down. Lower CER means a better biometric accuracy.
Role-BAC
Role based access control
Uses roles to manage rights and permissions for users. Roles are often implemented as groups. Think Microsoft security groups.
Admins have complete access
Executives have access to data on any project on server but can’t change server settings
Project managers have full control over their own projects but not any other teams projects
Team members can do work that project managers assign them but have little access outside of it.
Rule-BAC
Rule based access control
Uses rules. Common example is rules in routers and firewalls, which use access control lists to contain and organize the rules. Some rules are static, others might be modified on the spot.
DAC
Discretionary access control
Objects (files, folders, etc) have an owner, the owner establishes access for the objects. Example is NTFS used in windows, which allows users and administrators to restrict access to files and folders with permissions.
SID
Security identifier. Used in windows discretionary access control. Long string of characters used to identify users.
MAC (not network)
Mandatory access control
Uses labels to determine access. Admins assign labels to objects and users. If the labels match, then the user has access. Example SELinux. A lattice chart is used to layout the scheme.
ABAC
Attribute-based access control
Evaluates attributes and grants access based on the value of these attributes. Example, Homer has attributes employee, inspector, nuclear aware. A file server has a share called inspector, that grants access to the folder for any user that has the attributes employee, inspector, nuclear aware.
Many SDNs use ABAC schemes instead of rules on physical routers.
Conditional access
Used with traditional access control schemes but adds additional capabilites with if then statements. Policies in conditional access use signals which are similar to attributes in an ABAC scheme. Implemented in Microsoft azure active directory.
Jump server
Hardened server used to access and manage devices in another network with a different security zone.
Screened subnet
Aka DMZ. Buffered zone between a private network and the internet. Will contain some internet facing servers surrounded by firewalls such that the internal network is protected.
Network address translation gateway
Hosts NAT and provides internal clients with private IPs a path to the internet.
Zero trust network
Doesn’t trust any device by default even if the device was previously verified. Security model based on the principle of Zero trust. Can be implemented by requiring multifactor authentication.
UTM
Unified threat management
Single solution that combines multiple security controls. An appliance that performs URL filtering, malware inspection, content inspection, DDoS mitigation, etc
MSP
Managed Service provider. A cloud service provider that provides network connectivity managment, backup and disaster ecovery, growth management and planning
MSSP
Managed Security Service Provider. A cloud service provider for firewall management, patch managemnt, security audits, emergency response.
Fog computing
Cloud that’s close to your data. Cloud + IOT = Fog computing. Immeditate data stays local so no latency. No bandwith requirements. Privdate data never leaves - minimizes security concerns. Local decisons made from local data.
Eslasticity
Scale up, down, out and in as it is required (automatically)