CVE-2017-7486 in PostgreSQL
Summary
by MITRE
PostgreSQL versions 8.4 - 9.6 are vulnerable to information leak in pg_user_mappings view which discloses foreign server passwords to any user having USAGE privilege on the associated foreign server.
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Analysis
by VulDB Data Team • 09/07/2025
The vulnerability identified as CVE-2017-7486 represents a significant information disclosure flaw in PostgreSQL database systems affecting versions 8.4 through 9.6. This issue resides within the pg_user_mappings view which is designed to provide information about user mappings for foreign data wrappers. The flaw allows unauthorized users to access sensitive authentication credentials that should remain protected. The vulnerability specifically impacts systems utilizing foreign data wrappers where users have been granted USAGE privileges on foreign servers but should not have access to the underlying password information stored in the user mappings.
The technical implementation of this vulnerability stems from insufficient access controls within the pg_user_mappings view. When users possess USAGE privilege on a foreign server, they can query the pg_user_mappings system view to retrieve password information associated with user mappings. This occurs because the view does not properly enforce privilege checks to ensure that only authorized administrators can access the password credentials. The flaw exists in the database's privilege management system where the distinction between legitimate administrative access and unauthorized credential retrieval is not properly maintained. This type of vulnerability falls under CWE-284 which specifically addresses improper access control and weak privilege management in database systems.
The operational impact of this vulnerability extends beyond simple information disclosure as it can lead to complete system compromise when attackers gain access to foreign server credentials. An attacker with USAGE privileges on a foreign server can escalate their privileges and potentially gain access to remote databases or systems that are connected through the foreign data wrapper. This creates a chain reaction where a relatively low-privilege user can access sensitive data from remote systems without proper authentication. The vulnerability particularly affects organizations that rely on foreign data wrappers for integration with external databases, cloud services, or other systems where credentials are stored in the pg_user_mappings view. Attackers can leverage this information to perform lateral movement within the network or to access additional systems that depend on the same authentication credentials.
Security professionals should implement several mitigation strategies to address this vulnerability. The most immediate solution involves upgrading to PostgreSQL versions 10.0 or later where this vulnerability has been resolved through proper access control enforcement in the pg_user_mappings view. Organizations should also implement strict privilege management policies ensuring that USAGE privileges are granted only to trusted administrators and that regular audits are conducted to verify proper access controls. Additionally, database administrators should review existing user mappings and ensure that unnecessary foreign server access is revoked. The mitigation aligns with ATT&CK technique T1078 which addresses legitimate credentials and privilege escalation through proper access control enforcement. Organizations should also consider implementing network segmentation and monitoring for unauthorized access attempts to foreign data wrapper configurations. Regular security assessments should verify that the fix has been properly implemented and that no additional access control loopholes exist in the database configuration.