CVE-2026-110181 in PostgreSQL Anonymizer
Summary
by MITRE • 10/28/2026
PostgreSQL Anonymizer contains a vulnerability related to anonymization functions defined using SQL-standard function bodies. PostgreSQL analyses such functions at declaration time, while Anonymizer only attempts to check them at execution time. This problem can be exploited by any user with the TEMPORARY privilege. The issue is fixed in PostgreSQL Anonymizer 3.3.0 and later versions.
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Analysis
by VulDB Data Team • 10/28/2026
The vulnerability identified within the PostgreSQL Anonymizer extension stems from a fundamental mismatch between how standard SQL functions are validated during their creation phase versus when they are executed at runtime. In typical database operations, functions defined with SQL-standard bodies undergo static analysis by the database engine upon declaration to ensure syntactic correctness and basic semantic validity. However, the specific implementation in PostgreSQL Anonymizer relies on dynamic checks that occur only when the function is actually invoked during data processing. This architectural decision creates a window of opportunity for exploitation because the extension fails to validate critical security constraints or input sanitization rules at the time of function definition, leaving potentially malicious or malformed logic undetected until execution begins.
This design flaw allows any user possessing the TEMPORARY privilege on the database instance to define and subsequently exploit these anonymization functions without requiring elevated administrative rights. The attacker can craft a SQL function that appears valid under standard PostgreSQL rules but contains logic designed to bypass intended data masking or obfuscation mechanisms. By leveraging this discrepancy, an unauthorized actor can manipulate the output of anonymized queries, potentially exposing sensitive personal information or internal database structures that were supposed to remain hidden. This represents a significant breach in data privacy controls, as the core purpose of the Anonymizer extension is to ensure compliance with regulations such as GDPR by preventing direct access to raw PII (Personally Identifiable Information).
From a classification perspective, this issue aligns closely with CWE-20 Improper Input Validation and CWE-749 Exposed Dangerous Method. The failure to validate function bodies at declaration time constitutes an improper input validation error because the system accepts inputs that do not meet expected security criteria until it is too late to prevent execution. Furthermore, the ability for lower-privileged users to execute code with unintended side effects relates to access control weaknesses where privilege boundaries are insufficiently enforced during dynamic code evaluation. In terms of offensive tactics, this vulnerability facilitates techniques associated with ATT&CK T1059 Command and Scripting Interpreter, as it allows an attacker to inject custom logic into the database environment that executes within the context of the database process, potentially leading to further lateral movement or data exfiltration if combined with other exploits.
The operational impact of this vulnerability is severe for organizations relying on PostgreSQL Anonymizer for compliance-driven data masking workflows. If exploited, it undermines the integrity of anonymization processes, meaning that reports generated from masked datasets may still contain identifiable information. This not only violates privacy policies but also exposes the organization to legal and regulatory penalties. Additionally, because the exploitation requires only TEMPORARY privilege, which is often granted by default or easily obtained in shared development environments, the attack surface is broad and accessible to a wide range of internal users who might otherwise be considered low-risk actors.
To mitigate this risk, organizations must immediately upgrade PostgreSQL Anonymizer to version 3.3.0 or any later release where these validation checks have been corrected to occur at declaration time rather than execution time. Until the upgrade is performed, database administrators should restrict TEMPORARY privilege creation for users who do not strictly require it and audit existing function definitions within temporary schemas for suspicious logic patterns. Implementing strict role-based access control policies that limit which roles can create or alter functions in public or shared namespaces further reduces the likelihood of exploitation. Regular security audits focusing on dynamic SQL execution paths are also recommended to identify similar architectural mismatches in other database extensions.