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Incident Handling. COEN 250. Definitions. Event – An observable occurrence Adverse Events – Events with negative consequences Computer Security Incident: traditional
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Incident Handling COEN 250
Definitions • Event – An observable occurrence • Adverse Events – Events with negative consequences • Computer Security Incident: • traditional • security-related adverse event in which there was a loss of data confidentiality, disruption of data or system integrity, or disruption or denial of availability • newer • a violation or imminent threat of violation of computer security policies, acceptable use policies, or standard security practices
Incident Types • CIA related incidents: • Confidentiality • Integrity • Availability • Other Types • Reconnaissance Attacks • Repudiation • Someone takes action and denies it later on.
Need for Incident Response • All organizations • Systematic response to incidents • Help in recovering quickly and efficiently • Prepare for handling and avoidance of future incidents • Deal properly with legal issues • Federal Agencies • Federal Information Security Management Act (FISMA) of 2002 • Provide “procedures for detecting, reporting, and responding to security incidents” • Establishes centralized Federal information security incident center. • Civilian agency • Establish point of contact (POC) with FedCIRC (Federal Computer Incident Reporting Center ) • OMB’s Circular No. A-130, Appendix III • Capability to provide help to users when an incident occurs
Incident Response Scope • Technical: • Incident detection and investigation tools and procedures • Management-related • Policy • Formation of incident response capability • In-house vs. out-sourced
Stake Holders • Organization’s ability to fulfill mission • Users • Administrators (Organization’s ISP) • Providers • Software vendors • Telecommunications providers • Third Party • Clients • Affected external party • Other incident response teams • Owner of attacking address • Reporting Agencies • Media • Law Enforcement Agencies • Incident Reporting Agencies
Incident Response Policy • Typical elements • Statement of management commitment • Purpose and objectives of the policy • Scope of the policy (to whom and what it applies and under what circumstances) • Definition of computer security incidents and their consequences • Organizational structure and delineation of roles, responsibilities, and levels of authority • Includes confiscation / disconnection of equipment • Monitoring of activity • Requirements for reporting • Prioritization or severity ratings of incidents • Performance measures • Reporting and contact forms.
Sharing Information with Outside Parties • Media • Establish media communications procedures • Designate single Point of Contact (PoC) • Prepare for media interaction • Do not reveal sensitive, technical information • Appreciate the importance to communicate the public fully and effectively • Brief media contacts on issues and sensitivities before discussion with media
Sharing Information with Outside Parties • Law Enforcement • Which agency? • Federal investigatory agencies • FBI • US Secret Service • State law enforcement • Local law enforcement • Office of the Inspector General (OIG) for federal agencies
Sharing Information with Outside Parties • Law Enforcement • What incidents? • Discuss beforehand. • How to report • Discuss beforehand. • Collection of evidence • What? • How?
Sharing Information with Outside Parties • Incident Reporting Organizations • Federal agencies only to FedCIRC • Information Analysis Infrastructure Protection (IAIP) • CERT® Coordination Center (CERT®/CC). • Information Sharing and Analysis Centers (ISAC)
Incident Response Team Structure • Team Models • Central Incident Response Team • Distributed Incident Response Teams • Coordinating Team • Provides guidance and advice • Does not have authority • Staffing Models • Employees • Partially outsourced • Fully outsourced
Incident Response Team Structure • Criteria • In house: • Need for 24/7 availability • Full time vs. part time team members • Volunteer fire department model • Employee morale • Incident response demands on-call responsibilities for most team members • Cost • Staff Expertise • Organizational structure of the organizations
Incident Response Team Structure • Criteria • Outsourcer • Current and Future Quality of Work • Division of Responsibilities • Sensitive Information Revealed to the Contractor • Lack of Organization-Specific Knowledge • Lack of Correlation • Outsourcer requires administrative access to systems and to logs • Location • Incident response often requires physical presence
Incident Response Team Structure • Team Development • Budget for training, publications, references • Mentoring program • Rotation between incident response and other duties • Training exercises
Incident Response Team Structure • Interactions with other groups • Management • Support, buy-in • Information security staff • Telecommunications staff • Some incidents involve unauthorized access to telephone lines • IT support staff • Legal department • Public affairs / media relations • Human resources • Business continuity planning • Physical security and facilities management
Incident Response Team Structure • Incident response team services • Determine the scope of the incident response team • Incident response • Advisory distribution • Vulnerability assessment • Intrusion detection • Education and awareness • Technology watch • Patch management • Usually not recommended
Incident Handling Detection and Analysis Preparation Containment, Eradication and Recovery Post-incident activity
Incident Handling: Preparation • Incident Handler Communications and Facilities • Contact information On-call information for other teams within the organization, including escalation information Incident reporting mechanisms • Pagers or cell phones to be carried by team members for off-hour support, onsite communications • Encryption software • War room for central communication and coordination • Secure storage facility for securing evidence and other sensitive materials
Incident Handling: Preparation • Incident Analysis Hardware and Software • Computer forensic workstations and/or backup devices to create disk images, preserve log files, and save other relevant incident data • Blank portable media • Easily portable printer • Packet sniffers and protocol analyzers • Computer forensic software • Floppies and CDs with trusted versions of programs to be used to gather evidence from systems • Evidence gathering accessories • hard-bound notebooks • digital cameras • audio recorders • chain of custody forms • evidence storage bags and tags • evidence tape
Incident Handling: Preparation • Incident Analysis Resources • Port lists, including commonly used ports and Trojan horse ports • Documentation for OSs, applications, protocols, and intrusion detection and antivirus signatures • Network diagrams and lists of critical assets, such as Web, e-mail, and File Transfer Protocol (FTP) servers • Baselines of expected network, system and application activity • Cryptographic hashes of critical files to speed the analysis, verification, and eradication of incidents
Incident Handling: Preparation • Incident Mitigation Software • Media, including OS boot disks and CD-ROMs, OS media, and application media • Security patches from OS and application vendors • Backup images of OS, applications, and data stored on secondary media
Incident Handling: Detection and Analysis • Incident Categories • Denial of Service • Malicious code • Unauthorized access • Inappropriate usage • Multiple component incidents
Incident Handling: Detection and Analysis • Signs of an incident • Intrusion detection systems • Antivirus software • Log analyzers • File integrity checking • Third-party monitoring of critical services • Incident indications vs. precursors • Precursor is a sign that an incident may occur in the future • E.g. scanning • Indication is a sign that an incident is occurring or has occurred
Incident Handling: Detection and Analysis • Indication of incident is no proof that incident has occurred • Number of indications exceedingly high • Recommendations • Profile networks and systems • Understand normal behavior • Use centralized logging and create a log retention policy • Perform event correlation • Keep hosts synchronized (Network time protocol) • Run packet sniffers
Incident Handling: Detection and Analysis • Incident documentation • If incident is suspected, start recording facts • Incident Prioritization based on • Current and potential technical effects • Criticality of affected resources • Incident notification • CIO • Head of information system • Local information security officer • Other incident teams • Other agency departments such as HR, public affairs, legal department
Incident Handling: Containment, Eradication, Recovery • Containment strategies • Vary based on type of incident • Criteria for choosing strategy include • Potential damage / theft of resources • Need for evidence information • Service availability • Resource consumption of strategy • Effectiveness of strategy • Duration of solution
Incident Handling: Containment, Eradication, Recovery • Evidence gathering • For incident analysis • For legal proceedings • Chain of custody • Authentication of evidence
Incident Handling: Containment, Eradication, Recovery • Attacker identification • Validation of attacker IP address • Scanning attacker’s system • Research attacker through search engines • Using Incident Databases • Monitoring possible attacker communication channels
Incident Handling: Containment, Eradication, Recovery • Eradication • Deleting malicious code • Disabling breached user accounts • Recovery • Restoration of system(s) to normal operations • Restoring from clean backups • Rebuilding systems from scratch • Replacing compromised files • Installing patches • Changing passwords • Tighten perimeter security • Strengthen logging
Incident Handling: Post-Incident Activity • Evidence Retention • Prosecution of attacker • Data retention policies • Cost
Denial of Service Incidents • DoS prevents authorized used of IT resources • Crashing OS through malformed TCP/IP packets • Crashing an application through malformed requests • Consume available resources • Network • Memory • Disk space
Denial of Service Incidents • DoS prevents authorized used of IT resources • Crashing OS through malformed TCP/IP packets • Crashing an application through malformed requests • Consume available resources • Network • Memory • Disk space
Denial of Service Attacks • Reflector attack • Spoof source address • Responder floods system with that source address • Double reflector attacks
Port 7 is echo – reflection service If DNS server responds echoed packet, a loop is possible
Denial of Service Attacks • Amplifier attacks
Denial of Service Attacks • Distributed Denial of Service
Denial of Service Attacks • Syn Floods
Denial of Service Attacks • Preparation • Talk with organization’s ISP • Filtering / limiting traffic • Coordinated response through CERT / FedCIRC • Intrusion detection software to detect DoS and DDoS • Resource monitoring • Internet health monitoring • Monitoring of WWW response times
Denial of Service Attacks • Incident prevention • Perimeter configuration • Block use of services that no longer serve a legitimate purpose • Perform ingress and egress filtering • Implement rate limiting • Use host hardening (disable services) • Implement DoS prevention software • Implement redundancy for services
Denial of Service Attacks • Detection and Analysis • Precursors • Reconnaissance activity • Newly released DoS tool • Indications
Denial of Service Attacks • Network-based DoS against a particular host • User reports of system unavailability • Unexplained connection losses • Network intrusion detection alerts • Host intrusion detection alerts (until the host is overwhelmed) • Increased network bandwidth utilization • Large number of connections to a single host • Asymmetric network traffic pattern (large amount of traffic going to the host, little traffic coming from the host) • Firewall and router log entries • Packets with unusual source addresses
Denial of Service Attacks • Network-based DoS against a network • User reports of system and network unavailability • Unexplained connection losses • Network intrusion detection alerts • Increased network bandwidth utilization • Asymmetric network traffic pattern (large amount of traffic entering the network, little traffic leaving the network) • Firewall and router log entries • Packets with unusual source addresses • Packets with nonexistent destination addresses
Denial of Service Attacks • DoS against the operating system of a particular host • User reports of system and application unavailability • Network and host intrusion detection alerts • Operating system log entries • Packets with unusual source addresses • DoS against an application on a particular host • User reports of application unavailability • Network and host intrusion detection alerts • Application log entries • Packets with unusual source addresses
Denial of Service Attacks • Containment, Eradication, and Recovery • Correct vulnerability that is being exploited • Implement filtering • Relocate target • Do not Hack Back
Denial of Service Attacks • Evidence Gathering • Identifying the Source of Attacks From Observed Traffic • Tracing Attacks Back Through ISPs • Learning How the Attacking DDoS Hosts Were Compromised • Reviewing a Large Number of Log Entries
Malicious Code • Malicious Code Types • Viruses • File infectors • Boot sector viruses • Macro viruses • Virus hoaxes • Trojan horses • Worms • Mobile code • Blended • Email • Windows shares • Web server attacks (Nimda) • Web clients (Nimda)
Malicious CodeIncident Preparation • User awareness • Subscribe to antivirus vendor bulletins • Deploy host-based intrusion detection systems to critical hosts • IDS detects • Configuration changes (Registry, …) • System executable modifications • Black list Trojan horse ports • Ineffective, because • There are too many ports • Newer trojan horses can be configured for any port
Malicious CodeIncident Prevention • Use of antivirus software • Block suspicious attached files • Configure email clients to act more securely • No preview, no automatic opening, no execution, … • Limit the use of non-essential programs with file transfer capabilities • P2P file & music sharing • Instant messaging • IRC clients / servers • Educate users on safe handling of email attachments • Eliminate open windows shares • Infection can quickly spread from one system to many others. • Prevent incoming / outgoing traffic on NetBIOS ports • Use web browser setting to limit mobile code
Malicious CodeDetection • Precursors • Alerts for software that the organization uses • Antivirus software quarantines files • Indications • Many different categories