---
id: CVE-2026-114649
title: >-
  Authentication bypass via issuer-and-serial-only certificate equality in
  shared cluster cache
summary: >-
  The MongoDB C# Driver compares TLS client certificates by issuer and serial
  number only when deciding whether two clients can share cached connections. In
  an application that creates clients from certificates supplied by different
  users,…
severity: medium
cvss: 6.8
cvssVector: 'CVSS:3.1/AV:N/AC:H/PR:L/UI:N/S:U/C:H/I:H/A:N'
cvssSource: cna
cwe:
  - CWE-1025
vendor: MongoDB
product: C# Driver
affected:
  - c_driver >= 1.8.0 < 3.13.0
published: '2026-10-22'
updated: '2026-10-22'
sourceUpdated: '2026-10-22T20:38:21.959Z'
source: CVEORG
sourceUrl: 'https://www.cve.org/CVERecord?id=CVE-2026-114649'
references:
  - url: 'https://jira.mongodb.org/browse/CSHARP-6184'
  - url: 'https://github.com/mongodb/mongo-csharp-driver/releases/tag/v3.13.0'
  - url: >-
      https://github.com/mongodb/mongo-csharp-driver/security/advisories/GHSA-6gjm-424r-3jh2
tags:
  - cve.org
ingestedAt: '2026-10-22T22:00:50.431Z'
---

## Overview

The MongoDB C# Driver compares TLS client certificates by issuer and serial number only when deciding whether two clients can share cached connections. In an application that creates clients from certificates supplied by different users, a user who provides a certificate copying another user's issuer and serial number, without that user's private key, can be given connections authenticated with the other user's certificate. Database operations can then run under the other user's identity, affecting the confidentiality and integrity of data that identity can access.

## Affected

- `c_driver >= 1.8.0 < 3.13.0`

## Remediation

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