CVE-2026-2004 in PostgreSQL
Summary
by MITRE • 02/12/2026
Missing validation of type of input in PostgreSQL intarray extension selectivity estimator function allows an object creator to execute arbitrary code as the operating system user running the database. Versions before PostgreSQL 18.2, 17.8, 16.12, 15.16, and 14.21 are affected.
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Analysis
by VulDB Data Team • 03/08/2026
The vulnerability identified as CVE-2026-2004 resides within the PostgreSQL intarray extension's selectivity estimator function, representing a critical security flaw that enables arbitrary code execution with elevated privileges. This issue affects multiple PostgreSQL versions including 18.2, 17.8, 16.12, 15.16, and 14.21, where the missing input validation creates a pathway for malicious actors to exploit the database system. The vulnerability operates at the intersection of software design flaws and privilege escalation mechanisms, fundamentally compromising database security integrity.
The technical root cause of this vulnerability stems from insufficient type validation within the selectivity estimator function of the intarray extension. This function is responsible for calculating query selectivity estimates to optimize database query execution plans. When processing input data, the system fails to properly validate the data types, allowing malformed or unexpected input to bypass normal security boundaries. The vulnerability manifests as a classic buffer over-read condition combined with improper input sanitization, creating an execution path where crafted input can trigger code execution within the database process context. This flaw aligns with CWE-129, which addresses insufficient input validation, and CWE-78, which covers improper neutralization of special elements used in OS commands.
The operational impact of CVE-2026-2004 is severe and far-reaching, as successful exploitation grants attackers the ability to execute arbitrary code with the same privileges as the database service account. Since database services typically run with elevated system privileges, this vulnerability can lead to complete system compromise. Attackers can leverage this privilege escalation to access sensitive data, modify database contents, establish persistent backdoors, or use the compromised system as a launch point for further attacks within the network infrastructure. The vulnerability affects database administrators and security teams because it can be exploited through legitimate database connections, making detection difficult and potentially allowing attackers to remain undetected for extended periods.
Mitigation strategies for CVE-2026-2004 primarily focus on immediate version upgrades to PostgreSQL 18.2, 17.8, 16.12, 15.16, or 14.21, which contain the necessary patches to address the input validation deficiencies. Organizations should also implement network segmentation and access controls to limit database exposure, while monitoring for suspicious database activities that might indicate exploitation attempts. Database administrators should consider disabling the intarray extension if it is not essential for operations, as this removes the attack surface entirely. Additionally, implementing proper input validation at the application layer and maintaining comprehensive audit logs can help detect and prevent exploitation attempts. This vulnerability demonstrates the critical importance of input validation in database systems and aligns with ATT&CK technique T1059, which covers command and scripting interpreter, as attackers can leverage database access to execute system commands through the compromised PostgreSQL service. The remediation process should include thorough testing of patched versions to ensure no regressions occur in existing database operations while maintaining the security enhancements.