Malicious Activity Flashcards
Objective 2.4 - Page 267
DoS (Denial of Service) Definition
Used to describe an attack that attempts to make a computer or server’s resources unavailable
DDoS (Distributed Denial of Service) Variants
DoS, Amplified DDoS, Reflected DDoS
DNS Attack Types
- DNS Cache Poisoning
- DNS Amplification
- DNS Tunneling
- Domain Hijacking
- DNS Zone Transfer
Directory Traversal Attacks
Exploiting insufficient security validation of user-supplied input file names
Privilege Escalation Attack
Exploiting system vulnerability to gain elevated access
Replay Attacks
Type of network-based attack where valid data transmissions are maliciously or fraudulently re-broadcast, repeated, or delayed
Involves intercepting data, analyzing it, and deciding whether to retransmit it later
Application - Email \ Online shopping \ social media
Session Hijacking
Attacker takes over a user session to gain unauthorized access
Replay Vs Session Hijacking
- In a Session Hijack, the attacker alters real-time data transmission
- In a Replay Attack, the attacker intercepts the data and then can decide later whether to retransmit the data
Malicious Code Injection Attacks
Introduction of harmful code into a program or system
Indicators of Compromise (IoC)
(Examples listed)
Account lockout
Concurrent session usage
Blocked content
Impossible travel
Resource consumption
Inaccessibility
Out-of-cycle logging
Published documents indicating hacking
Missing logs
Ping Flood (Flood Attacks type)
Overloading a server with ICMP echo requests (pings)
Mitigation - often countered by blocking echo replies
SYN Flood (Flood Attacks type)
Initiating multiple TCP sessions but not completing the 3-way handshake and consumes server resources and prevents legitimate connections
Mitigation \ Countermeasures
- Flood guard \ Timeout configurations \ Intrusion Prevention systems.
Permanent Denial of Service (PDOS) Attack
Exploits security flaws to break a networking device permanently by re-flashing its firmware
Requires a full firmware reload to bring the device back online
Fork Bomb
Attack creates a large number of processes, consuming processing power
Not considered a worm, as it doesn’t infect programs or use the network
Self-replicating nature causes a denial of service condition
DNS Amplification
Specialized DDoS that allows an attacker to initiate DNS requests from a spoof IP address to flood a website
Surviving and Preventing DoS \ DDoS Attacks (page 270)
- Black Hole or Sinkhole
- IPS
- Elastic Cloud Infrastructure
- Specialized Cloud Service Providers
Black Hole or Sinkhole (Surviving and Preventing DoS\DDoS)
Routes attacking IP traffic to a non-existent server through a null interface and it is effective but temporary solution
DNS Cache Poisoning (DNS Spoofing)
Corrupts a DNS resolver’s cache with false information and redirects users to malicious websites
Mitigation - Use DNSSED (Domain Name System Security Extensions) to add digital signatures to DNS data
Mitigation - Implement secure network configurations and firewalls to protect DNS servers
DNS Amplification Attacks
Overwhelms a target system with DNS response traffic by exploiting the DNS resolution process
Spoofed DNS queries sent to open DNS servers
Mitigation - Limit the size of DNS responses \ Rate limit DNS response traffic to reduce the impact
DNS Tunneling
Encapsulates non-DNS traffic (e.g., HTTP, SSH) over port 53
Attempts to bypass firewall rules for command and control or data exfiltration
Mitigation - Monitor and analyze DNS logs for unusual patterns indicating tunneling
Domain Hijacking (Domain Theft)
Unauthorized change of domain registration
May lead to loss of website control and redirection to malicious sites
DNS Zone Transfer Attacks
Attempts to obtain an entire DNS zone data copy
Exposes sensitive information about a domain’s network infrastructure
Could be used for reconnaissance in future attacks
Directory Traversal Attack
- An injection attack occurs when the attacker inserts malicious code through an application interface
- Application attack that allows access to commands, files, and directories that may or may not be connected to the web document root directory
- Attackers may use encoding to hide directory traversal attempts (%2e%2e%2f represents . . / )
File Inclusion
Web application vulnerability that allows an attacker either to download a file from an arbitrary location on the host file system or to upload an executable or script file to open a backdoor