CVE-2017-7546 in PostgreSQL
Summary
by MITRE
PostgreSQL versions before 9.2.22, 9.3.18, 9.4.13, 9.5.8 and 9.6.4 are vulnerable to incorrect authentication flaw allowing remote attackers to gain access to database accounts with an empty password.
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Analysis
by VulDB Data Team • 01/09/2021
PostgreSQL versions prior to 9.2.22, 9.3.18, 9.4.13, 9.5.8, and 9.6.4 contain a critical authentication flaw that enables remote attackers to bypass password validation and gain unauthorized access to database accounts. This vulnerability stems from a flaw in the authentication process where the system fails to properly validate empty passwords, creating a security loophole that allows malicious actors to authenticate using blank credentials. The issue manifests when the database server accepts connections from users who have not set a password, effectively granting full access to database resources without proper authentication. This vulnerability represents a significant risk to database security as it undermines the fundamental principle of access control and authentication. The flaw is classified as a weakness in authentication mechanisms and aligns with CWE-287, which addresses improper authentication vulnerabilities. From an operational perspective, this vulnerability exposes organizations to potential data breaches, unauthorized data access, and privilege escalation attacks. Attackers can exploit this weakness remotely without requiring any prior knowledge of valid passwords, making the attack surface particularly dangerous. The vulnerability affects multiple major PostgreSQL versions and represents a widespread issue across the database ecosystem. This authentication bypass allows threat actors to perform read, write, and administrative operations on the affected databases, potentially leading to data exfiltration, modification, or complete system compromise. The impact extends beyond simple unauthorized access as it can enable attackers to establish persistent backdoors, escalate privileges, and conduct further reconnaissance within the network infrastructure. Organizations using affected PostgreSQL versions face significant compliance risks as this vulnerability violates security standards such as those outlined in the NIST Cybersecurity Framework and ISO 27001 requirements for access control. The vulnerability demonstrates a critical failure in the authentication subsystem and represents a classic example of insufficient validation of user credentials. From an attacker's perspective, this flaw provides an easy path to database compromise with minimal effort required, making it particularly attractive for automated exploitation campaigns. The issue affects both new installations and existing deployments that have not been updated to patched versions, creating a broad attack surface across enterprise environments. This vulnerability directly relates to the ATT&CK technique T1078.004 which covers valid accounts and T1190 which addresses exploit public-facing application, as it allows unauthorized access through legitimate authentication mechanisms. The security implications are particularly severe for organizations handling sensitive data, as database credentials are often the primary target for attackers seeking persistent access to enterprise systems. The flaw underscores the importance of timely patch management and proper authentication configuration. Organizations should immediately implement mitigation strategies including updating to patched versions, enforcing strong password policies, and monitoring for unauthorized access attempts. Database administrators should also consider implementing additional security controls such as network segmentation, connection limiting, and comprehensive audit logging to detect and prevent exploitation attempts. The vulnerability highlights the critical need for robust authentication mechanisms and proper credential management practices within database environments. This flaw represents a fundamental breakdown in the security model and emphasizes the necessity of thorough testing and validation of authentication processes in database systems.