PgBouncer is a lightweight connection pooler for PostgreSQL that occupies a critical middleware position between applications and databases, sitting directly in the data path of many deployments. Vulnerabilities affecting the vendor skew toward serious outcomes, with an elevated share reaching critical severity; the recurring weakness classes—NULL-pointer dereferences, improper authentication, certificate validation flaws, and input-handling issues including SQL injection and cross-site scripting—reflect the authentication gateway and SQL-parsing demands of a pooler handling untrusted client connections. Defenders should treat PgBouncer updates as high-priority given its role in database access control; live severity and exploitation figures are shown alongside this summary.
The number and severity of CVEs published that impact products developed by Pgbouncer over time
Signals from CVEs in this vendor scope (11 CVEs).
11 CVEs · Highest risk first
| CVE | Published | CVSS | Risk | KEV | Exploit |
|---|---|---|---|---|---|
CVE-2026-6665CRITICAL The SCRAM code in PgBouncer before 1.25.2 did not check the return value of strlcat() correctly when building the contents of the SCRAM client-final-message. A malicious backend th | May 9, 2026 | 9.8 | 38 | NO | NO |
CVE-2026-6664HIGH An integer overflow in network packet parsing code in PgBouncer before 1.25.2 bypasses a boundary check and can lead to a crash. An unauthenticated remote attacker can crash PgBoun | May 9, 2026 | 7.5 | 32 | NO | NO |
CVE-2025-2291CRITICAL Password can be used past expiry in PgBouncer due to auth_query not taking into account Postgres its VALID UNTIL value, which allows an attacker to log in with an already expired p | Apr 16, 2025 | 9.8 | 30 | NO | NO |
CVE-2026-6666HIGH A possible null pointer reference in PgBouncer before 1.25.2 could lead to a crash, if a server sends an error response without SQLSTATE field. | May 9, 2026 | 7.5 | 29 | NO | NO |
CVE-2025-12819HIGH Untrusted search path in auth_query connection handler in PgBouncer before 1.25.1 allows an unauthenticated attacker to execute arbitrary SQL during authentication via a malicious | Dec 3, 2025 | 8.1 | 29 | NO | NO |
CVE-2021-3935HIGH When PgBouncer is configured to use "cert" authentication, a man-in-the-middle attacker can inject arbitrary SQL queries when a connection is first established, despite the use of | Nov 22, 2021 | 8.1 | 27 | NO | NO |
CVE-2015-4054HIGH PgBouncer before 1.5.5 allows remote attackers to cause a denial of service (NULL pointer dereference and crash) by sending a password packet before a startup packet. | May 23, 2017 | 7.5 | 24 | NO | NO |
CVE-2026-6667MEDIUM PgBouncer before 1.25.2 did not perform an appropriate authorization check for the KILL_CLIENT admin command. All users with access to the administration console (which itself requ | May 9, 2026 | 4.3 | 23 | NO | NO |
CVE-2021-3672MEDIUM A flaw was found in c-ares library, where a missing input validation check of host names returned by DNS (Domain Name Servers) can lead to output of wrong hostnames which might pot | Nov 23, 2021 | 5.6 | 22 | NO | NO |
CVE-2015-6817HIGH PgBouncer 1.6.x before 1.6.1, when configured with auth_user, allows remote attackers to gain login access as auth_user via an unknown username. | May 23, 2017 | 8.1 | 21 | NO | NO |
Signals from CVEs in this vendor scope (11 CVEs).
An overview of all social media posts that mention a CVE ID that affects a product developed by Pgbouncer.
Media articles that mention a CVE ID that affects a product developed by Pgbouncer — matched by CVE ID, not by vendor name.