Oracle Database Security Checklist for 2026

 

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.