Implementing Oracle Database Security

1. Implementing Oracle Database Security

2. Objectives • After completing this lesson, you should be able to do the following: • Describe your DBA responsibilities for security • Implement security by applying the principle of least privilege • Manage default user accounts • Implement standard password security features • Describe database auditing • Describe Virtual Private Database (VPD)

3. Industry Security Requirements • Legal: • Sarbanes-Oxley Act (SOX) • Health Information Portability and Accountability Act (HIPAA) • California Breach Law • UK Data Protection Act • Auditing

4. Separation of Responsibilities • Users with DBA privileges must be trusted. Consider: • Abuse of trust • Audit trails protect the trusted position. • DBA responsibilities must be shared. • Accounts must never be shared. • The DBA and the system administrator must be different people. • Separate operator and DBA responsibilities.

5. Database Security • A secure system ensures the confidentiality of the data that it contains. There are several aspects of security: • Restricting access to data and services • Authenticating users • Monitoring for suspicious activity

6. Principle of Least Privilege • Install only required software on the machine. • Activate only required services on the machine. • Give OS and database access to only those users that require access. • Limit access to the root or administrator account. • Limit access to the SYSDBA and SYSOPER accounts. • Limit users’ access to only the database objects required to do their jobs.

7. Applying the Principle of Least Privilege • Protect the data dictionary: • Revoke unnecessary privileges from PUBLIC: • Restrict the directories accessible by users. • Limit users with administrative privileges. • Restrict remote database authentication: O7_DICTIONARY_ACCESSIBILITY=FALSE REVOKE EXECUTE ON UTL_SMTP, UTL_TCP, UTL_HTTP,UTL_FILE FROM PUBLIC; REMOTE_OS_AUTHENT=FALSE

8. Managing Default User Accounts • DBCA expires and locks all accounts, except: • SYS • SYSTEM • SYSMAN • DBSNMP • For a manually created database, lock and expire any unused accounts.

9. Implementing Standard Password Security Features Password history Account locking User Setting up profiles Password aging and expiration Password complexity verification

10. Supplied Password Verification Function: VERIFY_FUNCTION • The supplied password verification function enforces these password restrictions: • The minimum length is four characters. • The password cannot be the same as the username. • The password must have at least one alphabetic, one numeric, and one special character. • The password must differ from the previous password by at least three letters. • Tip: Use this function as a template to createyour own customized password verification.

11. Creating a Password Profile

12. Assigning Users to a Password Profile • Select Administration > Schema > Users & Privileges > Users.

13. Where We Are • Comparing security aspects • Applying the principle of least privilege • Managing default user accounts • Implementing standard password security features • Creating and using password profiles • Auditing • Virtual Private Database (VPD)

14. Monitoring for Suspicious Activity • Monitoring or auditing must be an integral part of your security procedures. Review the following: • Mandatory auditing • Standard database auditing • Value-based auditing • Fine-grained auditing (FGA) • DBA auditing

15. Enterprise Manager Audit Page

16. Standard Database Auditing • Enable database auditing. Parameter file User DBA executes command. (2) Specify audit options. Database Server process Audit options Generate audit trail. Audittrail (3) Review auditinformation. (4) Maintain audit trail. OS or XML audit trail

17. Uniform Audit Trails STATEMENTID, ENTRYID AUDIT_TRAIL=DB,EXTENDED DBA_AUDIT_TRAIL DBA_FGA_AUDIT_TRAIL EXTENDED_TIMESTAMP, PROXY_SESSIONID, GLOBAL_UID, INSTANCE_NUMBER, OS_PROCESS, TRANSACTIONID, SCN, SQL_BIND, SQL_TEXT DBA_COMMON_AUDIT_TRAIL

18. Enhanced Enterprise User Auditing Exclusive schema Shared schema Standard audit USERNAME Standard audit USERNAME GLOBAL_UID Fine-grained audit DB_USER Fine-grained audit DB_USER GLOBAL_UID

19. Value-Based Auditing Trigger fires. A user makes a change. Audit record is created by the trigger. User’s change is made. And it is inserted into an audit trail table.

20. Fine-Grained Auditing • Monitors data access on the basis of content • Audits SELECT, INSERT, UPDATE, DELETE, and MERGE • Can be linked to a table or view, to one or more columns • May fire a procedure • Is administered with the DBMS_FGA package Policy: AUDIT_EMPS_SALARY SELECT name, salary FROM employees WHERE department_id = 10; employees

21. FGA Policy dbms_fga.add_policy ( object_schema => 'HR', object_name => 'EMPLOYEES', policy_name => 'audit_emps_salary', audit_condition=> 'department_id=10', audit_column => 'SALARY', handler_schema => 'secure', handler_module => 'log_emps_salary', enable => TRUE, statement_types=> 'SELECT' ); • Defines: • Audit criteria • Audit action • Is created with DBMS_FGA .ADD_POLICY SELECT name, job_id FROM employees; SELECT name, salary FROM employees WHERE department_id = 10; SECURE.LOG_ EMPS_SALARY employees

22. Audited DML Statement: Considerations • Records are audited if FGA predicate is satisfied and relevant columns are referenced. • DELETE statements are audited regardless of any specified columns. • MERGE statements are audited with the underlying INSERT or UPDATE generated statements. UPDATE hr.employees SET salary = 10 WHERE commission_pct = 90; UPDATE hr.employees SET salary = 10 WHERE employee_id = 111;

23. FGA Guidelines • To audit all statements, use a null condition. • Policy names must be unique. • The audited table or view must already exist when you create the policy. • If the audit condition syntax is invalid, an ORA-28112 error is raised when the audited object is accessed. • If the audited column does not exist in the table, no rows are audited. • If the event handler does not exist, no error is returned and the audit record is still created.

24. DBA Auditing • Users with the SYSDBA or SYSOPER privileges can connect when the database is closed: • Audit trail must be stored outside the database. • Connecting as SYSDBA or SYSOPER is always audited. • Enable additional auditing of SYSDBA or SYSOPER actions with audit_sys_operations. • Control audit trail with audit_file_dest.

25. Maintaining the Audit Trail • The audit trail should be maintained. Follow best practice guidelines: • Review and store old records • Prevent storage problems • Avoid loss of records

26. Quiz: What Is Audited? • Match the following text, “A” to “What is Audited?”, and “T” to “What is in the Audit Trail?”. • A1: Data changed by DML statements • A2: SQL statements (insert, update, delete, select, and merge) based on content) • A3: Privilege use including object access • T1:Fixed set of data including the SQL statement • T2: Fixed set of data • T3: N/A

27. Where We Are • Comparing security aspects • Applying the principle of least privilege • Managing default user accounts • Implementing standard password security features • Describing auditing: • Mandatory auditing • Standard database auditing • Value-based auditing • Fine-grained auditing • DBA auditing • Virtual Private Database (VPD)

28. Virtual Private Database: Overview • Virtual Private Database (VPD) consists of: • Fine-grained access control • Secure application context • VPD uses policies to add conditions to SQL statements that protect sensitive data. • VPD provides row-level access control. • Application attributes defined inside an application context are used by fine-grained access policies.

29. VPD Example • Business rule: Employees outside the HR department are only allowed to see their own EMPLOYEES record. A salesman enters the following query: • SELECT * FROM EMPLOYEES; • The function implementing the security policy returns the predicate employee_id='my_emp_id' and the database rewrites the query and executes the following: • SELECT * FROM EMPLOYEES • WHERE employee_id='my_emp_id‘;

30. Creating a Column-Level Policy BEGIN dbms_rls.add_policy(object_schema => 'hr', object_name => 'employees', policy_name => 'hr_policy', function_schema =>'hr', policy_function => 'hrsec', statement_types =>'select,insert', sec_relevant_cols=>'salary,commission_pct'); END; /

31. Column-Level VPD: Example • Statements are not always rewritten. • Consider a policy protecting the SALARY and COMMISSION_PCT columns of the EMPLOYEES table. The fine-grained access control is: • Not enforced for this query: • Enforced for these queries: SQL> SELECT last_name FROM employees; SQL> SELECT last_name, salary 2 FROM employees; SQL> SELECT * FROM employees;

32. Security Updates • Oracle posts security alerts on the Oracle Technology Network Web site at:http://www.oracle.com/technology/deploy/security/alerts.htm • Oracle database administrators and developers can also subscribe to be notified about critical security alerts via e-mail by clicking the “Subscribe to Security Alerts Here” link.

33. Applying Security Patches • Use the Critical Patch Update process. • Apply all security patches and workarounds. • Contact the Oracle security products team.

34. Summary • In this lesson, you should have learned how to: • Describe your DBA responsibilities for security • Apply the principle of least privilege • Manage default user accounts • Implement standard password security features • Describe database auditing • Describe Virtual Private Database (VPD)

35. Practice Overview: Implementing Oracle Database Security • This practice covers the following topics: • Expiring passwords every 60 days • Locking accounts after a grace period of 10 days • Not allowing the reuse of passwords for 1,800 days • Forcing accounts to lock for 10 minutes after four failed login attempts