Denial of Service Vulnerability in PgBouncer Affects Multiple Versions
CVE-2026-107349

7.5HIGH

Key Information:

Vendor

PgBouncer

Status
Pgbouncer
Vendor
CVE Published:
14 October 2026

What is CVE-2026-107349?

A vulnerability in PgBouncer from versions 1.20.0 to 1.26.0 creates a condition where an unauthenticated remote attacker can trigger an infinite loop. This occurs when a StartupMessage contains an options parameter with an empty name, leading to an endless lookup in the ignore_startup_parameters list. Given that PgBouncer operates with a single process for all clients, this flaw allows the affected system's CPU core to be saturated, resulting in complete unresponsiveness to all client requests until the process is manually restarted.

Affected Version(s)

PgBouncer 1.20.0 < 1.26.1

References

https://www.pgbouncer.org/changelog.html

CVSS V3.1

Score:
7.5
Severity:
HIGH
Confidentiality:
None
Integrity:
None
Availability:
None
Attack Vector:
Network
Attack Complexity:
Low
Privileges Required:
None
User Interaction:
None
Scope:
Unchanged

Timeline

  • Vulnerability published

  • Vulnerability Reserved

Credit

Thanks to Jackds Security (@jackds-security) for finding and reporting this issue.
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