Vulnerability-Lookup

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

Vulnerability from cvelistv5 – Published: 2026-10-14 17:34 – Updated: 2026-10-16 14:18

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

1 reference

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

Impacted products

1 product

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

JSON

To clipboard

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FKIE_CVE-2026-107350

Vulnerability from fkie_nvd - Published: 2026-10-14 18:17 - Updated: 2026-10-16 15:17

Severity

8.8 (High) - CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H

Summary

References

	URL	Tags
	f86ef6dc-4d3a-42ad-8f28-e6d5547a5007	https://www.pgbouncer.org/changelog.html

Impacted products

	Vendor	Product	Version

JSON

To clipboard

{
  "affected": [
    {
      "affectedData": [
        {
          "defaultStatus": "unaffected",
          "product": "PgBouncer",
          "vendor": "n/a",
          "versions": [
            {
              "lessThan": "1.26.1",
              "status": "affected",
              "version": "1.17.0",
              "versionType": "semver"
            }
          ]
        }
      ],
      "source": "f86ef6dc-4d3a-42ad-8f28-e6d5547a5007"
    }
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    }
  ],
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GHSA-QCXP-3CX5-3F3G

Vulnerability from github – Published: 2026-10-14 18:32 – Updated: 2026-10-14 18:32

Details

Severity

8.8 (High)


                  
                    CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H

Show details on source website

JSON

To clipboard

{
  "affected": [],
  "aliases": [
    "CVE-2026-107350"
  ],
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    ],
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    "severity": "HIGH"
  },
  "details": "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.",
  "id": "GHSA-qcxp-3cx5-3f3g",
  "modified": "2026-10-14T18:32:29Z",
  "published": "2026-10-14T18:32:29Z",
  "references": [
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2026-107350"
    },
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      "type": "WEB",
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      "type": "CVSS_V3"
    }
  ]
}

MSRC_CVE-2026-107350

Vulnerability from csaf_microsoft - Published: 2026-10-16 01:05 - Updated: 2026-10-17 01:48

Summary

Authentication bypass via second StartupMessage during SCRAM authentication in PgBouncer

Scope

1 vulnerability in this advisory, including CVE-2026-107350.

CVE-2026-107350

8.8 (High)


                
                  CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H

Fixed: 1 product Known affected: 1 product

https://learn.microsoft.com/en-us/azure/azure-linux/tutoria…

Open the full advisory

Sightings

Author	Source	Type	Date	Other

Nomenclature

Seen: The vulnerability was mentioned, discussed, or observed by the user.
Confirmed: The vulnerability has been validated from an analyst's perspective.
Published Proof of Concept: A public proof of concept is available for this vulnerability.
Exploited: The vulnerability was observed as exploited by the user who reported the sighting.
Patched: The vulnerability was observed as successfully patched by the user who reported the sighting.
Not exploited: The vulnerability was not observed as exploited by the user who reported the sighting.
Not confirmed: The user expressed doubt about the validity of the vulnerability.
Not patched: The vulnerability was not observed as successfully patched by the user who reported the sighting.

Vulnerability timeline

Sightings and recorded dates, grouped by day · UTC

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The MITRE ATT&CK techniques below are AI-generated suggestions, inferred from the description of the vulnerability by the CIRCL/vulnerability-attack-technique-classification-roberta-base model, served locally by ML-Gateway. They have not been verified by an analyst and are provided for guidance only.
The approach is described in our paper Mapping CVEs to MITRE ATT&CK Techniques: A Curated Gold-Set Classifier and the Limits of LLM-Assisted Label Expansion.
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CVE-2026-107350 (GCVE-0-2026-107350)

FKIE_CVE-2026-107350

GHSA-QCXP-3CX5-3F3G

MSRC_CVE-2026-107350

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Vulnerability timeline

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