TCP Dangerous Database

Port 5432 (PostgreSQL)

Learn about port 5432 (PostgreSQL) - security risks, vulnerabilities, and common uses. Find devices with port 5432 open.

Quick Info

Port Number

5432

Protocol

TCP

Service

PostgreSQL

IANA Name

PostgreSQL

Service Description

TCP port 5432 is the default port for PostgreSQL, a powerful, open-source object-relational database system (ORDBMS). PostgreSQL implements the client/server model. Clients connect to the PostgreSQL server to execute SQL queries and manage database objects. The protocol used is a custom protocol designed for client-server communication, allowing for features such as authentication, query execution, transaction management, and data transfer. The connection begins with a startup message from the client, identifying the database and user. The server responds with authentication challenges, which may involve password authentication, Kerberos, or other methods. Once authenticated, the client can send SQL queries to the server. The server parses, analyzes, and executes these queries, returning the results to the client. The protocol supports various data types and encoding formats to ensure data integrity and compatibility between the client and server.

At a technical level, PostgreSQL's communication is based on a message-oriented protocol. Messages are structured as a header followed by a payload. The header contains information such as the message type and length. The payload contains the actual data being transmitted. The protocol supports various message types, including queries, responses, notifications, and authentication requests. The server manages multiple concurrent connections using a process-per-connection architecture. Each client connection is handled by a dedicated server process, allowing for parallel query execution and improved performance. The server also employs various caching mechanisms to optimize query performance and reduce disk I/O. The protocol is designed to be extensible, allowing for the addition of new features and data types without breaking compatibility with older clients and servers.

## Firewall Recommendations

It is generally recommended to block port 5432 from the public internet. Access to the PostgreSQL server should be restricted to authorized clients only, typically within a private network or through a VPN. If remote access is necessary, use a secure tunnel such as SSH tunneling or a VPN to encrypt the traffic and protect the database credentials. Implement strong authentication mechanisms, such as password policies and multi-factor authentication, to prevent unauthorized access. Regularly audit and update the PostgreSQL server to patch security vulnerabilities. Consider using a firewall to allow access only from specific IP addresses or networks. Monitor the PostgreSQL server logs for suspicious activity and intrusion attempts. Employ network segmentation to isolate the database server from other critical systems, limiting the impact of a potential breach.

Security Information

Exposing port 5432 directly to the internet poses significant security risks. Attackers can exploit vulnerabilities in PostgreSQL itself, such as SQL injection flaws or authentication bypasses, to gain unauthorized access to the database. Brute-force attacks targeting weak passwords are also a common threat. If the server is not properly configured, attackers can use vulnerabilities to execute arbitrary code on the server, potentially compromising the entire system. Furthermore, if the server is running with default configurations or weak authentication methods, it becomes an easy target for automated scanning and exploitation. Data breaches, data corruption, and denial-of-service attacks are potential consequences of a compromised PostgreSQL server.

Known Vulnerabilities

CVE	Name	Severity	Description
CVE-2023-39417	PostgreSQL: Privilege Escalation Vulnerability in pg_read_server_files	Medium	An authenticated attacker can leverage the pg_read_server_files role to read any file on the server's file system, potentially leading to privilege escalation.
CVE-2018-1058	PostgreSQL: CREATE DATABASE allows bypass of intended security restrictions	Medium	CREATE DATABASE allows bypass of intended security restrictions because a database owner can execute arbitrary code as the database system user.
CVE-2014-8161	PostgreSQL: Unspecified vulnerability in pg_upgrade	Medium	Unspecified vulnerability in pg_upgrade in PostgreSQL before 9.0.20, 9.1.x before 9.1.15, 9.2.x before 9.2.11, 9.3.x before 9.3.7, and 9.4.x before 9.4.2 allows attackers to execute arbitrary code with superuser privileges via vectors involving a pg_control file.