CVE-2026-84970

A numeric truncation weakness exists in the JSON parsing component of the MongoDB C++ Driver's BSON library. An actor who controls the text that an embedding application hands to the library's public JSON parsing interface, when that text is very large, can cause the library to read memory beyond the supplied buffer and return it to the caller, to silently accept only part of the input as a complete document, or to terminate the process. No MongoDB server, credentials, or non-default configuration is required; the effect is confined to the process that uses the library.

CVSS v3 6.2 MEDIUM

6.2^/10

CVSS v3 : MEDIUM

Vector :

Exploitability : 1.4 / Impact : 4.7

Attack Vector LOCAL

Attack Complexity HIGH

Privileges Required NONE

User Interaction NONE

Confidentiality Impact LOW

Integrity Impact LOW

Availability Impact HIGH

Scope UNCHANGED

References

Link	Resource
https://jira.mongodb.org/browse/CXX-3547	Vendor Advisory Issue Tracking

Configurations

Configuration 1 (hide)

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

History

No history.

Information

Published : 2026-09-03 15:17

Updated : 2026-09-10 19:47

NVD link : CVE-2026-84970

Mitre link : CVE-2026-84970

CVE.ORG link : CVE-2026-84970

JSON object : View

Products Affected

mongodb

c\+\+_driver

CWE

CWE-681

Incorrect Conversion between Numeric Types

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