CVE-2026-84965

An integer wraparound in an allocation size calculation in the BSON library's JSON parsing code can cause a buffer to be released while a following copy operation still writes through the stale pointer. On builds where sizes are 32 bits, an unauthenticated party able to supply a sufficiently large JSON input to an application that links the library may cause that application to terminate unexpectedly, resulting in denial of service.

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/CDRIVER-6405	Vendor Advisory

Configurations

Configuration 1 (hide)

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

History

22 Sep 2026, 16:00

Type	Values Removed	Values Added
References	~~() https://jira.mongodb.org/browse/CDRIVER-6405 -~~	() https://jira.mongodb.org/browse/CDRIVER-6405 - Vendor Advisory
CPE		cpe:2.3:a:mongodb:c_driver::::::mongodb::*
First Time		Mongodb c Driver Mongodb

Information

Published : 2026-09-03 16:18

Updated : 2026-09-22 16:00

NVD link : CVE-2026-84965

Mitre link : CVE-2026-84965

CVE.ORG link : CVE-2026-84965

JSON object : View

Products Affected

mongodb

c_driver

CWE

CWE-190

Integer Overflow or Wraparound

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