CVE-2026-81528

A MongoDB C# driver document-replacement code path omits the element-name/shape validation that the equivalent write paths apply, so a value supplied as a replacement is forwarded to the server without neutralization of query-language special elements. An application that passes untrusted, loosely-typed input as a replacement value therefore allows that input to be interpreted by the database as update logic rather than as data, executing under the application's own database credentials. Applications using strongly-typed document mappings are not affected.

CVSS v3 5.4 MEDIUM

5.4^/10

CVSS v3 : MEDIUM

Vector :

Exploitability : 2.8 / Impact : 2.5

Attack Vector NETWORK

Attack Complexity LOW

Privileges Required LOW

User Interaction NONE

Confidentiality Impact LOW

Integrity Impact LOW

Availability Impact NONE

Scope UNCHANGED

References

Link	Resource
https://jira.mongodb.org/browse/CSHARP-6158
https://www.nuget.org/packages/MongoDB.Driver/3.11.1

Configurations

No configuration.

History

No history.

Information

Published : 2026-08-27 20:18

Updated : 2026-08-28 21:16

NVD link : CVE-2026-81528

Mitre link : CVE-2026-81528

CVE.ORG link : CVE-2026-81528

JSON object : View

Products Affected

No product.

CWE

CWE-943

Improper Neutralization of Special Elements in Data Query Logic

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