---
id: CVE-2026-81530
title: >-
  A weakness in the client-side encryption configuration surface of the MongoDB
  C# Driver causes sensitive key-management credential material supplied by the
  application to be reproduced verbatim in the driver's human-readable
  diagnostic r…
summary: >-
  A weakness in the client-side encryption configuration surface of the MongoDB
  C# Driver causes sensitive key-management credential material supplied by the
  application to be reproduced verbatim in the driver's human-readable
  diagnostic r…
severity: medium
cvss: 5.6
cvssVector: 'CVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:C/C:H/I:N/A:N'
cwe:
  - CWE-532
vendor: mongodb
product: c#_driver
affected:
  - 'c#_driver >= 2.10.0, < 3.11.1'
patched:
  - c#_driver 3.11.1
published: '2026-08-27'
updated: '2026-09-29'
sourceUpdated: '2026-09-29T19:16:13.963'
source: NVD
sourceUrl: 'https://nvd.nist.gov/vuln/detail/CVE-2026-81530'
references:
  - url: 'https://jira.mongodb.org/browse/CSHARP-6164'
    label: cna@mongodb.com
  - url: 'https://www.nuget.org/packages/MongoDB.Driver/3.11.1'
    label: cna@mongodb.com
tags:
  - nvd
epss: 0.00091
epssPercentile: 0.00456
ingestedAt: '2026-09-29T19:44:04.118Z'
---

## Overview

A weakness in the client-side encryption configuration surface of the MongoDB C# Driver causes sensitive key-management credential material supplied by the application to be reproduced verbatim in the driver's human-readable diagnostic representation of its client settings, instead of being masked as other secret fields are. A party able to read the application's logs, diagnostic output, or a process memory dump may thereby recover the plaintext credentials and use them to decrypt protected field data.

## Affected

- `c#_driver >= 2.10.0, < 3.11.1`

## Remediation

Upgrade past the affected range:

- `c#_driver 3.11.1`