CVE-2026-84966

An incorrect numeric type conversion in the BSON document building component of the MongoDB C++ Driver may cause a length value to be interpreted incorrectly. When an application supplies an extremely large, non-terminated field name to the builder, the library may read memory outside the intended buffer and terminate the calling process. No authentication is required, but the calling application must pass the oversized name in a specific form.

CVSS v3 5.1 MEDIUM

5.1^/10

CVSS v3 : MEDIUM

Vector :

Exploitability : 1.4 / Impact : 3.6

Attack Vector LOCAL

Attack Complexity HIGH

Privileges Required NONE

User Interaction NONE

Confidentiality Impact NONE

Integrity Impact NONE

Availability Impact HIGH

Scope UNCHANGED

References

Link	Resource
https://jira.mongodb.org/browse/CXX-3548	Vendor Advisory

Configurations

Configuration 1 (hide)

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

History

22 Sep 2026, 15:54

Type	Values Removed	Values Added
First Time		Mongodb c\+\+ Driver Mongodb
References	~~() https://jira.mongodb.org/browse/CXX-3548 -~~	() https://jira.mongodb.org/browse/CXX-3548 - Vendor Advisory
CPE		cpe:2.3:a:mongodb:c\+\+_driver::::::mongodb::*

Information

Published : 2026-09-03 16:18

Updated : 2026-09-22 15:54

NVD link : CVE-2026-84966

Mitre link : CVE-2026-84966

CVE.ORG link : CVE-2026-84966

JSON object : View

Products Affected

mongodb

c\+\+_driver

CWE

CWE-681

Incorrect Conversion between Numeric Types

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