CVE-2025-12819 is a vulnerability identified in PgBouncer, a popular lightweight connection pooler for PostgreSQL databases. The issue arises from an untrusted search path in the auth_query connection handler, which processes authentication queries. Specifically, before version 1.25.1, PgBouncer improperly handles the search_path parameter in the StartupMessage sent by clients during authentication. An attacker can craft a malicious search_path to inject and execute arbitrary SQL commands without authentication. This leads to a critical security breach, as arbitrary SQL execution can compromise database confidentiality, integrity, and availability. The vulnerability has a CVSS 3.1 score of 7.5, indicating high severity, with attack vector network-based, attack complexity high, privileges required low, no user interaction, and impacts on confidentiality, integrity, and availability. Although no exploits are currently known in the wild, the vulnerability's nature makes it a significant risk for organizations using PgBouncer in their PostgreSQL environments. The flaw can be exploited remotely, making it a prime target for attackers seeking to gain unauthorized database access or disrupt services. The vulnerability was reserved in early November 2025 and published in December 2025, with the PostgreSQL community assigning the CVE and tracking its status. No official patches or exploit code links were provided in the initial disclosure, but upgrading to PgBouncer 1.25.1 or later is the recommended remediation.

For European organizations, this vulnerability poses a substantial risk to database security, especially those relying on PostgreSQL with PgBouncer for connection pooling. Successful exploitation can lead to unauthorized data disclosure, data manipulation, or denial of service, affecting business operations and regulatory compliance, including GDPR. Critical sectors such as finance, healthcare, government, and telecommunications could face severe disruptions or data breaches. The ability to execute arbitrary SQL without authentication increases the threat landscape, potentially enabling lateral movement within networks or persistent access. Given the widespread use of PostgreSQL and PgBouncer in Europe, the vulnerability could impact a broad range of enterprises and public institutions. The high attack complexity somewhat limits immediate exploitation but does not eliminate the risk, especially from skilled threat actors. The lack of known exploits currently provides a window for proactive defense, but organizations must act swiftly to prevent future attacks.

1. Upgrade PgBouncer to version 1.25.1 or later immediately to apply the fix for the untrusted search path vulnerability. 2. Restrict network access to PgBouncer instances by implementing firewall rules and network segmentation, limiting connections to trusted hosts only. 3. Monitor authentication logs and database activity for unusual or unauthorized SQL commands that could indicate exploitation attempts. 4. Employ application-layer firewalls or database activity monitoring tools to detect and block malicious queries targeting the search_path parameter. 5. Review and harden PostgreSQL and PgBouncer configuration settings, minimizing privileges and disabling unnecessary features. 6. Conduct regular security audits and vulnerability assessments focused on database infrastructure. 7. Educate database administrators and security teams about this vulnerability and the importance of timely patching. 8. Implement multi-factor authentication and strong access controls for database management interfaces to reduce risk of privilege escalation.