CVE-2026-107350 (GCVE-0-2026-107350)

Vulnerability from cvelistv5 – Published: 2026-10-14 17:34 – Updated: 2026-10-16 14:18
VLAI
Title
Authentication bypass via second StartupMessage during SCRAM authentication in PgBouncer
Summary
Improper authentication in PgBouncer 1.17.0 through 1.26.0 allows a remote attacker who knows the password of a user listed in auth_file to log in as any other user that authenticates using SCRAM, including PgBouncer admin users and backend superusers. A second StartupMessage sent during SCRAM authentication against a non-existent database is not rejected and switches the user being logged in as, while the SCRAM exchange is still verified against the keys of the first user.
Severity
8.8 (High)
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
SSVC
Exploitation: none Automatable: no Technical Impact: total
CISA Coordinator · CISA-ADP (v2.0.3)
Decision recorded 2026-10-16 03:56 UTC
CWE
  • CWE-287 - Improper Authentication
Assigner
PostgreSQL CNA under the redhat root
CNA scorecard C 67/100 over 88 records in the last 180 days details
References
Impacted products
Vendor Product Version CPE status
n/a PgBouncer Affected: 1.17.0 , < 1.26.1 (semver)
Credits
Thanks to Dave Aitel (@daveaitel-openai, OpenAI) for finding and reporting this issue.
Show details on NVD website
To clipboard 

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