CVE-2026-84969

A memory-handling error in the BSON-to-JSON conversion helpers of the MongoDB C Driver can write a small number of bytes past the end of a heap buffer when a binary field is encoded and the output is cut short at a caller-configured length limit. A party who supplies the document content, with no privileges on the application that links the driver, may cause a small amount of data outside the intended buffer to be altered.

CVSS v3 3.7 LOW

3.7^/10

CVSS v3 : LOW

Vector :

Exploitability : 2.2 / Impact : 1.4

Attack Vector NETWORK

Attack Complexity HIGH

Privileges Required NONE

User Interaction NONE

Confidentiality Impact NONE

Integrity Impact LOW

Availability Impact NONE

Scope UNCHANGED

References

Link	Resource
https://jira.mongodb.org/browse/CDRIVER-6410	Vendor Advisory Issue Tracking

Configurations

Configuration 1 (hide)

OR	cpe:2.3:a:mongodb:c_driver::::::mongodb::*
	cpe:2.3:a:mongodb:c_driver::::::mongodb::*

History

No history.

Information

Published : 2026-09-03 15:17

Updated : 2026-09-10 19:50

NVD link : CVE-2026-84969

Mitre link : CVE-2026-84969

CVE.ORG link : CVE-2026-84969

JSON object : View

Products Affected

mongodb

c_driver

CWE

CWE-787

Out-of-bounds Write

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