A flaw in the client-side encryption support of the MongoDB .NET/C# driver can cause data designated for client-side field-level encryption to be written without encryption. Under certain platform text-encoding configurations, an internal name conversion loses information, so the encryption layer fails to associate the operation with its configured encryption rules and the operation proceeds without an error being raised. An application user with the ability to write data through an affected application can therefore have sensitive fields persisted in plaintext, defeating the confidentiality guarantee that client-side encryption is intended to provide. No integrity or availability impact was observed.

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History

Fri, 23 Oct 2026 15:00:00 +0000

Type Values Removed Values Added
First Time appeared Mongodb
Mongodb c# Driver
Mongodb mongodb.libmongocrypt Nuget Package
Vendors & Products Mongodb
Mongodb c# Driver
Mongodb mongodb.libmongocrypt Nuget Package

Fri, 23 Oct 2026 00:45:00 +0000

Type Values Removed Values Added
Description A flaw in the client-side encryption support of the MongoDB .NET/C# driver can cause data designated for client-side field-level encryption to be written without encryption. Under certain platform text-encoding configurations, an internal name conversion loses information, so the encryption layer fails to associate the operation with its configured encryption rules and the operation proceeds without an error being raised. An application user with the ability to write data through an affected application can therefore have sensitive fields persisted in plaintext, defeating the confidentiality guarantee that client-side encryption is intended to provide. No integrity or availability impact was observed.
Title Plaintext exposure of encrypted fields via ANSI code-page corruption of database name
Weaknesses CWE-838
References
Metrics cvssV3_1

{'score': 5.9, 'vector': 'CVSS:3.1/AV:L/AC:H/PR:N/UI:N/S:C/C:H/I:N/A:N'}

cvssV4_0

{'score': 6.9, 'vector': 'CVSS:4.0/AV:L/AC:L/AT:P/PR:N/UI:N/VC:H/VI:N/VA:N/SC:H/SI:N/SA:N'}


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cve-icon MITRE

Status: PUBLISHED

Assigner: mongodb

Published:

Updated: 2026-10-22T21:38:04.057Z

Reserved: 2026-10-21T21:57:49.528Z

Link: CVE-2026-114650

cve-icon Vulnrichment

No data.

cve-icon NVD

Status : Received

Published: 2026-10-22T19:17:38.837

Modified: 2026-10-22T22:18:05.883

Link: CVE-2026-114650

cve-icon Redhat

No data.

cve-icon OpenCVE Enrichment

Updated: 2026-10-23T14:40:21Z

Weaknesses