---
id: CVE-2026-107350
title: >-
  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
  back…
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
  back…
severity: high
cvss: 8.8
cvssVector: 'CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H'
cwe:
  - CWE-287
  - CWE-841
vendor: Red Hat
product: PgBouncer
affected:
  - PgBouncer >= 1.17.0 < 1.26.1
patched:
  - hardened_images
published: '2026-10-14'
updated: '2026-10-16'
sourceUpdated: '2026-10-16T15:17:04.897'
source: NVD
sourceUrl: 'https://nvd.nist.gov/vuln/detail/CVE-2026-107350'
references:
  - url: 'https://www.pgbouncer.org/changelog.html'
    label: f86ef6dc-4d3a-42ad-8f28-e6d5547a5007
  - url: >-
      https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-107350.json
  - url: 'https://access.redhat.com/security/cve/CVE-2026-107350'
  - url: 'https://bugzilla.redhat.com/show_bug.cgi?id=2552733'
  - url: 'https://www.cve.org/CVERecord?id=CVE-2026-107350'
  - url: 'https://nvd.nist.gov/vuln/detail/CVE-2026-107350'
  - url: 'https://access.redhat.com/errata/RHSA-2026:83843'
tags:
  - nvd
  - cve.org
  - csaf
  - vex
  - red-hat
epss: 0.00369
epssPercentile: 0.30552
ssvc:
  exploitation: none
  automatable: 'no'
  technicalImpact: total
  timestamp: '2026-10-16T03:56:50.467564Z'
ingestedAt: '2026-10-14T18:47:39.310Z'
---

## Overview

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.

## Remediation

Refer to the linked advisories for vendor-supplied fixes and affected version ranges.

## Vendor advisories

- **Red Hat VEX** · Important · affected: Red Hat Hardened Images · no fix planned: Red Hat Hardened Images · updated 2026-10-15 · [vex](https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-107350.json)
- **RHSA-2026:83843** · Red Hat · fixed in: Red Hat Hardened Images · released 2026-10-16 · [advisory](https://access.redhat.com/errata/RHSA-2026:83843)