CVE-2026-6669 (GCVE-0-2026-6669)

Vulnerability from cvelistv5 – Published: 2026-09-23 16:04 – Updated: 2026-09-23 16:46
VLAI
Title
Unbounded SCRAM iteration count causes CPU exhaustion in PgBouncer
Summary
Missing upper bound on the key derivation iteration count accepted during SCRAM authentication to a backend server in PgBouncer through 1.25.2 allows a malicious or compromised PostgreSQL backend to cause uncontrolled CPU consumption in PgBouncer. The resulting key derivation cannot be interrupted in frontend builds such as PgBouncer. Because PgBouncer serves all clients from a single process, one backend can in this way stop it from serving traffic for every other database and client it is pooling, so the failure of a single backend is not contained.
Severity
5.9 (Medium)
CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:N/A:H
SSVC
Exploitation: none Automatable: no Technical Impact: partial
CISA Coordinator · CISA-ADP (v2.0.3)
Decision recorded 2026-09-23 16:33 UTC
CWE
  • CWE-400 - Uncontrolled Resource Consumption
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: 0 , ≤ 1.25.2 (semver)
Credits
Thanks to @HarutoKimura for finding and reporting this issue.
Show details on NVD website
To clipboard 

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