Introduction
For many organizations, database security is still associated with passwords and firewall rules. In reality, modern Oracle database security extends far beyond authentication.
In 2026, Oracle DBAs must secure databases against:
- Ransomware attacks
- Credential theft
- Privilege abuse
- SQL injection
- Insider threats
- Cloud misconfigurations
- AI-assisted cyberattacks
This article presents a practical security checklist based on real-world Oracle DBA operations and Oracle 23ai best practices.
Security Philosophy Every DBA Should Follow
I use a simple principle:
Assume the database will be attacked and design controls accordingly.
Security should not depend on a single layer.
A secure Oracle environment combines:
- Identity Security
- Network Security
- Data Security
- Monitoring
- Auditing
- Backup Protection
- Disaster Recovery
Layer 1 – User and Account Security
Review Default Accounts
Many environments still contain unused accounts.
Check:
SELECT username,
account_status
FROM dba_users
ORDER BY username;
Review:
- ANONYMOUS
- APEX_PUBLIC_USER
- DBSNMP
- OUTLN
- SYSTEM
Lock unused accounts.
ALTER USER username ACCOUNT LOCK;
DBA Recommendation
Perform quarterly user-account reviews.
Enforce Strong Password Policies
Use Oracle Profiles.
Example:
CREATE PROFILE SECURE_PROFILE
LIMIT
FAILED_LOGIN_ATTEMPTS 5
PASSWORD_LIFE_TIME 90
PASSWORD_REUSE_TIME 365;
Recommended:
| Setting | Value |
|---|---|
| Minimum Length | 14+ |
| Expiration | 90 Days |
| Failed Attempts | 5 |
| Complexity | Enabled |
Layer 2 – Privilege Security
Identify Powerful Users
Check privileged accounts:
SELECT *
FROM dba_role_privs
WHERE granted_role IN
('DBA',
'SYSDBA',
'SYSOPER');
Questions every DBA should ask:
- Does the user still need access?
- Is access temporary?
- Is access documented?
Avoid Granting DBA Role
Many organizations grant DBA role unnecessarily.
Instead:
Grant only required privileges.
Example:
GRANT CREATE SESSION TO app_user;
GRANT CREATE TABLE TO app_user;
Principle:
Least Privilege Access
Layer 3 – Network Security
Restrict Listener Access
Check listener configuration.
Review:
lsnrctl status
Ensure:
- Listener not exposed publicly
- Only application servers can connect
- Admin access restricted
Enable SQL*Net Encryption
Verify encryption settings.
SQLNET.ENCRYPTION_SERVER = REQUIRED
SQLNET.CRYPTO_CHECKSUM_SERVER = REQUIRED
Benefits:
- Data protection in transit
- Protection from packet sniffing
- Regulatory compliance
Layer 4 – Data Encryption
Verify Transparent Data Encryption (TDE)
TDE should be standard in 2026.
Check wallet:
SELECT wallet_type,
status
FROM v$encryption_wallet;
Expected:
OPEN
Benefits:
- Datafile encryption
- Backup encryption
- Regulatory compliance
Encrypt Sensitive Columns
Examples:
- Aadhaar numbers
- PAN numbers
- Credit card data
- Banking details
Implement column-level encryption where required.
Layer 5 – Auditing
Enable Unified Auditing
Verify:
SELECT value
FROM v$option
WHERE parameter='Unified Auditing';
Monitor:
- Login activity
- Failed logins
- Privilege grants
- Sensitive table access
Audit SYS Activities
Many breaches involve privileged accounts.
Example:
AUDIT ALL BY SYS;
Review regularly.
Layer 6 – Oracle 23ai SQL Firewall
Why SQL Firewall Matters
One of the most important security features introduced in recent Oracle releases.
SQL Firewall:
- Learns approved SQL patterns
- Blocks unauthorized SQL
- Protects against injection attacks
Ideal for:
- Banking applications
- ERP systems
- Customer portals
Layer 7 – Backup Security
Encrypt RMAN Backups
Example:
CONFIGURE ENCRYPTION FOR DATABASE ON;
Benefits:
- Backup theft protection
- Cloud storage security
- Compliance readiness
Validate Backup Recoverability
Never assume backups are usable.
Perform:
RESTORE VALIDATE DATABASE;
Monthly validation is recommended.
Layer 8 – Patch Management
Track Oracle Release Updates
Check version:
SELECT banner_full
FROM v$version;
Maintain:
- Quarterly RUs
- Security patches
- One-off critical fixes
My Patching Rule
If a patch fixes:
- Security vulnerability
- Data corruption issue
- RAC stability issue
It should be prioritized.
Layer 9 – Monitoring and Threat Detection
Monitor Failed Logins
Example:
SELECT username,
timestamp
FROM dba_audit_session
WHERE returncode <> 0;
Look for:
- Brute-force attacks
- Password guessing
- Service account misuse
Monitor Privilege Escalation
Track:
GRANT DBA;
GRANT SYSDBA;
GRANT ANY PRIVILEGE;
Unexpected grants should trigger alerts.
Layer 10 – Cloud Security (OCI)
For OCI-hosted databases:
Review:
IAM Policies
Follow least-privilege principles.
NSG Rules
Allow only required ports.
Common:
| Port | Purpose |
|---|---|
| 22 | SSH |
| 1521 | Listener |
| 5500 | EM Express |
Restrict source IPs.
OCI Vault
Store:
- TDE Keys
- Secrets
- API Keys
- Wallet Passwords
Never store secrets in scripts.
Layer 11 – Disaster Recovery Security
Review Data Guard configuration.
Verify:
SELECT protection_mode
FROM v$database;
Ensure:
- Standby database encrypted
- Backups encrypted
- DR access controlled
Security Health Scorecard
Every quarter I recommend reviewing:
| Control | Status |
|---|---|
| Default Accounts Reviewed | ✓ |
| Password Policy Verified | ✓ |
| TDE Enabled | ✓ |
| Unified Auditing Enabled | ✓ |
| RMAN Encryption Enabled | ✓ |
| SQL Firewall Enabled | ✓ |
| Listener Restricted | ✓ |
| Patching Current | ✓ |
| Backup Validation Tested | ✓ |
| DR Security Reviewed | ✓ |
Security Trends DBAs Must Watch in 2026
AI-Assisted Attacks
Attackers increasingly use AI tools to:
- Generate malicious SQL
- Automate vulnerability discovery
- Accelerate credential attacks
Zero Trust Database Security
Trust no user by default.
Continuously verify:
- Identity
- Device
- Access pattern
- Location
Security Automation
Future-ready DBAs automate:
- User reviews
- Privilege reviews
- Audit analysis
- Patch compliance
- Backup validation
Final Thoughts
Database security is no longer a yearly audit activity. It is an everyday operational responsibility.
A modern Oracle DBA must think like a security engineer, continuously reviewing access, encryption, auditing, backups, and cloud configurations.
In my experience, the strongest Oracle environments are not the ones with the most tools—they are the ones where security reviews are performed consistently and operational discipline is maintained.