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Learn about the essential controls implemented over hardware, data media, and operators in a computing facility to safeguard confidentiality, integrity, and availability. Explore categories and types of controls, from preventive to corrective, as well as key concepts like the Orange Book classifications and trusted facility management. Discover the importance of separation of duties, rotation of duties, trusted recovery, and modes of operation to enhance overall security measures.
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“Controls over the hardware in a computing facility, over the data media used, and over the operators using these resources.” Operations Security
C.I.A.as affected by Operations Controls Confidentiality: affect sensitivity & secrecy Integrity: how well implementation directly affects accuracy & authenticity Availability: affect system’s level of fault tolerance and recovery capability
Controls & Protections Controls used to protect hardware, software, & media from Threats in environment Internal or External Intruders Operators inappropriately accessing resources
Categories of Controls Preventative Controls are designed to lower amount & impact of unintentional errors Prevent unauthorized intruders from entering EX: prenumbered forms & data validation Detective Controls To detect an error once it has occurred After the fact Corrective (or Recovery) Controls Implemented to mitigate the loss Restoring data
Categories of Controls (conti) Deterrent Controls Encourage compliance, complement other controls Application Controls Designed into software to minimize & detect irregularities Transaction Controls Input Controls Processing Controls Output Controls Change Controls Test Controls
TCSEC “Orange Book” Controls D: Minimal Protection C: Discretionary Protection C1: Discretionary Security Protection C2: Controlled Access Protection B: Mandatory Protection B1:Labeled Security Protection B2: Structured Protection B3: Security Domains A1: Verified Protection
Orange Book Defines assurance requirements for secure computer operations Assurance: level of confidence that security policy has been correctly implemented Two types: Operational: basic features & architecture Life cycle: controls & standards used in operations & maintenance
Orange Book: Covert Channel Analysis Channel: info transfer path Covert channel: path that violates security policy Covert storage channel Covert timing channel TCSEC B2: must protect against, must perform analysis for all storage channels TCSEC B3 & A1: must protect against both types of convert channels
Orange Book:Trusted Facility Management Assignment of a specific individual to administer secruity related system functions Must take auditable action before being able to assume admin role B2: System must support separate operator & system admin roles B3: Must clearly identify functions of security admin
Orange Book:Separation of Duties Assignment of parts of task to different personnel No one person with total control == no one person that can completely compromise system “Two man control” Three distinct system admin roles System admin Security admin Enhanced operator
Orange Book:Rotation of Duties Limit amount of time any individual performs the same security related duties
Orange Book:Trusted Recovery Required only in B3 & A1 level systems System failure == serious security risk Security bypassed while not fully functional Ex: System crash while sensitive data written to disk before ACL changed Hierarchical Recovery Types Manual Recovery Automated Recovery of single failure Automated Recovery without undue loss
Modes of Operation Dedicated Mode Each user with any access has a valid personnel clearance, formal access approval (with signed non disclosure), & a valid “need to know” all info System-High Mode All above except need to know some info Compartmental Mode Need to know only info they have direct access to Multilevel Mode Some do not have valid clearance for all info but have clearance & need to know for info they will have access to
Change Control Manages process of tracking & approving changes Identify, control, audit Insure changes not diminish sys sec Document all changes Primary functions of change control Change implemented in orderly manner -- test Inform user base of change Analyze effect of the change Reduce negative impact of change
Procedures for Change Control Applying to introduce change Approval of change Cataloging intended change Testing change Scheduling & implementing change Reporting change to management
Configuration Management More formalized for highly sec system Configuration Managers Identify & document each functional & physical config item Personally assure approval for and manage all config changes Record & report status of changes Audit system config for unknown changes Configuration Control Board
Administrative Controls More to do with human than hardware or software Personnel Security Employment screening / background chk Mandatory vacations Job action warnings & terminations Separation of duties & responsibilities Least Privilege Need to know Change control Record retention & documentation control
Least Privilege Separate levels of access based on job function Three basic levels Read Only Read/Write: only to data copied from original location Access Change: original location
Operations Job Functions Computer Operator Operations analyst Job control analyst Production Scheduler Production Control Analyst Tape Librarian
Others Record Retention concerns Data remanence Info on media after it has been erased Due care & Due Diligence Legal, governmental, & simple good business practices Documentation Control Security plans, risk analysis, security policy, etc
Operations Controls Day-to-day procedures to protect Most important aspects of (details follow): Resource protection Hardware controls Software controls Privileged-entity controls Media controls Physical access controls
Resource Protection Protect from loss or compromise Hardware Lan Hardware, Storage Media, Processing Systems, Standalone Computers, Printers, etc Software Program Libraries & Source, Vendor Software, O/S & Utilities Data Backup Data, User Data Files, Password Files, Operating data directories, Sys logs
Hardware Controls Hardware maintenance Maintenance accounts Disabled until needed Preset, widely known ids & passwords Diagnostic port controls Ports for trouble shooting Hardware physical controls
Software Controls What software used on system Licensed software only Anti-virus management Software testing Software utilities Safe software storage Backup controls
Privileged-Entity Controls Oversight of personnel with “special” access to systems Examples of special access Lower level system commands Special operational parameters System control programs
Media Controls Media Security Logging, Access Control, & Proper Disposal Overwriting: a pattern, its compliment, then another pattern (0011, 1100, 1010) Degaussing & Destruction Media Viability Controls Protect viability of media used Marking, Handling, Storage, Orig. Quality Media Librarian
Physical Access Controls Hardware Control of comm. Equip, storage media, printed logs & reports Software Control of backup files, system logs, production apps, sensitive/critical data Some personnel need special physical access It department personnel, Cleaning Staff, Maintenance personnel, third-party contractors, consultants, temp staff Supervision Physical piggybacking – 2nd person follows 1st through door (man trap)
Monitoring & Auditing “Reviewing an operational system to see that controls, both manual & automated, are functioning effectively & correctly” Are technical features being bypassed Are required procedures being followed Is there evidence of abnormal computer usage
Monitoring Looking for: Illegal software installing Hardware faults & error states Operational events for abnormalities Techniques Intrusion detection Penetration testing Violation analysis
Intrusion Detection & Violation Analysis Sampling traffic patterns Look for activities above clipping level Clipping Level & Profile based anomaly detection Baseline of user activity considered “normal” Enables ignoring normal user errors When exceeded violation report filed Also used for variance detection Looking for Repetitive mistakes, individuals exceeding their authority, too many people with restricted access, patterns showing serious intrusion attempts
Penetration Testing Attempting to access a system from outside normal Technology based Scanning & probing Demon Dialing / War Driving Sniffing Personnel Oriented Dumpster Diving Social Engineering
Auditing Checking for internal & external compliance Patterns of abnormal use Audit these functions Backup controls System & transaction controls Data library procedures & center security Systems development standards Contingency plans
Audit Trails Enables tracing a transaction’s history Enforcement of accountability Audit Logs should record Transaction date & time, who processed it, & where Any security events relating to transaction Any commands (with options) executed by user All identification & authorization attempts Any files or other resources accessed Auditor should look for Amendments to production jobs Production job returns Computer operator practices
Security Goals of Audit Mechanism Allow review of patterns of access to individual objects Allow discovery of repeated attempts to bypass security mechanisms Find use of privileges by user greater than they should have An additional form of user assurance that attempt to bypass security will be caught
Audit Logs Prevent log file from being altered Protect availability of log during event Protect logging media from destruction or damage
Benefits of Auditing & Problem Management Enhancement of risk assessment program Enhancement of internal readiness & communications Personnel Security Training Reduced failures to manageable level Prevent (re)occurrence of problem Mitigate impact of violation
Threats Event that if realized can cause damage to system Accidental Loss Operator errors Transaction processing errors Inappropriate activities Inappropriate content Waste of corporate resources Sexual or racial harassment Abuse of privileges Illegal Computer Operations Eavesdropping Fraud, Theft, Sabotage External Attack
Vulnerabilities & Attacks Traffic / Trend analysis Analyze data characteristics & pattern rather than content Stop by: padding message, sending noise, covert channel analysis Maintenance Accounts Data-Scavenging Attacks Keyboard attacks & Laboratory Attacks Initial Program Load vulnerabilities Single user mode, boot sequence, bios, CD Social Engineering Network Address Hijacking