Back to the CVE list
CVE-2026-107350

Authentication bypass via second StartupMessage during SCRAM authentication in PgBouncer

CVSS score

8.8

EPSS probability

%0.4

Risk score

0.0

Published

4 d ago

A patch is available only for some products or versions

Kanıt listesindeki ürün ve sürüm eşleşmesini kontrol edin; bazı varyantlar hâlâ etkileniyor olabilir.

Impact on My Inventory

Only the personal products you have added to your account are assessed; an organisation's inventory does not appear here.

Checking session…

Vulnerability description

CVE AI research

The stored explanation is shown at once; refreshing evaluates the sources again.

DayBreach AI Explanation

Verified against sources

CVE-2026-107350: PgBouncer Authentication Bypass Vulnerability

Sources read

2

Source agreement

Tam uyum

Evidence confidence

%63

Short explanation

CVE-2026-107350 is an improper authentication flaw in PgBouncer versions 1.17.0 through 1.26.0 during SCRAM authentication. An attacker who knows a user password listed in auth_file can log in as any other user authenticating via SCRAM.

Why does it matter?

This vulnerability allows authentication bypass, potentially compromising critical accounts including PgBouncer admin users and backend superusers.

What should be done?

  • Follow vendor advisories and changelogs
  • Check vendor sources for applicable patch or update status
  • Review affected product versions
Chain of evidence and sources2 verified claims

PgBouncer 1.17.0 ile 1.26.0 sürümleri arasındaki yetersiz kimlik doğrulaması, SCRAM sırasında oturum açma atlatılmasına izin verir.

İkinci bir StartupMessage gönderilmesi, SCRAM değişimi ilk kullanıcının anahtarlarına karşı doğrulanırken kullanıcıyı değiştirir.

Show the technical text from the sources

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.

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

CWE: CWE-287

Explanation produced with the local gemini-flash-lite-latest model. Numerical metrics and the KEV, patch and exploit statuses are not determined by AI.

IMPACT: Affected Products and Software

Affected Products

The following products are affected by CVE-2026-107350 vulnerability. Where our threat engine knows the exact affected versions, they are listed below.

IDVENDORPRODUCTACTION
1n/aPgBouncer View
2debianpgbouncer (sid) View
3debianpgbouncer (forky) View
4debianpgbouncer (trixie) View
5debianpgbouncer (bookworm) View
Total affected vendors: 2|Products: 5

RED HAT CSAF/VEX: Product Impact Check

Red Hat has not yet published a CSAF/VEX impact record for this CVE. This does not mean “not affected”.

SCORING: CVSS from Multiple Sources

CVSS Scores

The Common Vulnerability Scoring System is a standardised framework for assessing the severity of vulnerabilities in software and systems. We collect and display CVSS scores from several sources for each CVE.

SCOREVERSIONSEVERITYVECTORSOURCE
8.8CVSS V3_1HIGHCVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:HCVE CNA
8.8CVSS V31HIGHCVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:HNVD

Patch and Remediation Guide

Solution & Remediation Advisory

Partial patch

1 düzeltme kanıtı bulundu; en az 3 ürün veya sürüm hâlâ etkileniyor ya da inceleniyor.

debianpgbouncer (sid)1.26.1-1

Debian sid: 1.26.1-1

Confirm the affected product and version against the source evidence above.
Restrict access to internet-facing services and apply network segmentation.
Apply the official update named in the evidence only to the matching product and version.
Monitor server logs and network endpoints for signs of anomalous execution.

Public exploit and active exploitation status

Verified exploit intelligence

No verified public PoC, exploit repository or Metasploit module has been found for this CVE yet.

Weakness Classification and Attack Patterns (CWE & CAPEC)

CWE - Common Weakness Enumeration

While CVE identifies specific instances of vulnerabilities, CWE categorises the common flaws or weaknesses that can lead to vulnerabilities. CVE-2026-107350 is associated with the following CWEs:

Common Attack Pattern Enumeration and Classification (CAPEC)

Common Attack Pattern Enumeration and Classification (CAPEC) stores attack patterns, which are descriptions of the common attributes and approaches employed by adversaries to exploit the CVE-2026-107350 weaknesses.

Attack Vector and Accessibility

ExposureAğ üzerinden
PermissionsLow
UserGerekmiyor

Official Sources and Advisories

CVSS Vector Radar Chart

8.8 / 10
Attack VectorNetworkComplexityLowPrivilegesLowUser Interact.NoneConfidentialityLowIntegrityNoneAvailabilityHigh

Vulnerability Scoring Details

CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
Attack VectorNetwork
Attack ComplexityLow
Privileges RequiredLow privileges
User InteractionNone required
Confidentiality (Gizlilik)Low
Integrity (Bütünlük)None
Availability (Erişilebilirlik)High

Kısmi yama

1 düzeltme kanıtı bulundu; en az 3 ürün veya sürüm hâlâ etkileniyor ya da inceleniyor.

Follow the vendor

N
n/a logo
n/a
D
debian logo
debian

Weakness Type (CWE & CAPEC)

Similar Vulnerabilities

Get this vulnerability through the API

Affected products, version ranges, exploitation status and patch information in a single request, with a free key.

curl -H "x-api-key: $DAYBREACH_API_KEY" \
  "https://api.daybreach.dev/api/v1/intel/cves/CVE-2026-107350"