Improper Authentication Vulnerability in PgBouncer by PgBouncer Team
CVE-2026-107350

8.8HIGH

Key Information:

Vendor

PgBouncer Team

Status
Pgbouncer
Vendor
CVE Published:
14 October 2026

What is CVE-2026-107350?

An improper authentication issue in PgBouncer versions 1.17.0 to 1.26.0 allows attackers with knowledge of a user's password to gain unauthorized access. This vulnerability permits remote attackers to authenticate as any user in the auth_file, including high-level administrative accounts. The flaw arises during the SCRAM authentication process where a second StartupMessage can inadvertently switch the logged-in user, compromising user integrity and access controls.

Affected Version(s)

PgBouncer 1.17.0 < 1.26.1

References

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

CVSS V3.1

Score:
8.8
Severity:
HIGH
Confidentiality:
High
Integrity:
High
Availability:
High
Attack Vector:
Network
Attack Complexity:
Low
Privileges Required:
Low
User Interaction:
None
Scope:
Unchanged

Timeline

  • Vulnerability published

  • Vulnerability Reserved

Credit

Thanks to Dave Aitel (@daveaitel-openai, OpenAI) for finding and reporting this issue.
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