CVE-2026-81527

A NoSQL/expression injection weakness exists in the LINQ-to-aggregation query translation layer of the MongoDB C# Driver, in both aggregation expression and query filter translation. When application-supplied values are embedded in certain query constructs, special elements contained within those values are not properly escaped before the resulting query is transmitted to the database, so portions of the value may be interpreted by the database as query logic rather than as data. A user able to supply values that an application incorporates into an affected query may thereby cause unintended data to be returned or query results to be altered.

CVSS v3 6.5 MEDIUM

6.5^/10

CVSS v3 : MEDIUM

Vector :

Exploitability : 3.9 / Impact : 2.5

Attack Vector NETWORK

Attack Complexity LOW

Privileges Required NONE

User Interaction NONE

Confidentiality Impact LOW

Integrity Impact LOW

Availability Impact NONE

Scope UNCHANGED

References

Link	Resource
https://jira.mongodb.org/browse/CSHARP-6156
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-2026-81527

Mitre link : CVE-2026-81527

CVE.ORG link : CVE-2026-81527

JSON object : View

Products Affected

No product.

CWE

CWE-943

Improper Neutralization of Special Elements in Data Query Logic

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