CVE-2026-81529

Improper neutralization of delimiters in connection-URL construction allows connection-option injection in the MongoDB C# Driver. When an application passes untrusted text into the driver's connection-URL builder and round-trips the builder back into a client configuration, the untrusted text is serialized without neutralizing the URL/option delimiters and is then re-parsed as authoritative connection options. A low-privileged user of such an application can thereby introduce or suppress security-relevant connection settings.

CVSS v3 7.1 HIGH

7.1^/10

CVSS v3 : HIGH

Vector :

Exploitability : 1.8 / Impact : 4.7

Attack Vector NETWORK

Attack Complexity HIGH

Privileges Required LOW

User Interaction NONE

Confidentiality Impact HIGH

Integrity Impact LOW

Availability Impact NONE

Scope CHANGED

References

Link	Resource
https://jira.mongodb.org/browse/CSHARP-6171	Vendor Advisory
https://www.nuget.org/packages/MongoDB.Driver/3.11.1	Product

Configurations

Configuration 1 (hide)

cpe:2.3:a:mongodb:c\#_driver:*:*:*:*:*:mongodb:*:*

History

29 Sep 2026, 19:16

Type	Values Removed	Values Added
First Time		Mongodb c\# Driver Mongodb
CPE		cpe:2.3:a:mongodb:c\#_driver::::::mongodb::*
References	~~() https://jira.mongodb.org/browse/CSHARP-6171 -~~	() https://jira.mongodb.org/browse/CSHARP-6171 - Vendor Advisory
References	~~() https://www.nuget.org/packages/MongoDB.Driver/3.11.1 -~~	() https://www.nuget.org/packages/MongoDB.Driver/3.11.1 - Product

Information

Published : 2026-08-27 20:18

Updated : 2026-09-29 19:16

NVD link : CVE-2026-81529

Mitre link : CVE-2026-81529

CVE.ORG link : CVE-2026-81529

JSON object : View

Products Affected

mongodb

c\#_driver

CWE

CWE-88

Improper Neutralization of Argument Delimiters in a Command ('Argument Injection')

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