CVE-2026-106437

The BSON buffer-reservation API in the MongoDB C Driver can record a length smaller than the five-byte BSON minimum. Later append or comparison operations can underflow unsigned length calculations and read or write outside the document buffer. An actor who can influence the length supplied by an embedding application can cause the application to terminate or read or corrupt adjacent process memory. Reaching this issue requires the application to pass an undersized value to bson_reserve_buffer and then perform an affected operation.

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/CDRIVER-6423	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

27 Oct 2026, 19:56

Type	Values Removed	Values Added
First Time		Mongodb c Driver Mongodb
References	~~() https://jira.mongodb.org/browse/CDRIVER-6423 -~~	() https://jira.mongodb.org/browse/CDRIVER-6423 - Vendor Advisory, Issue Tracking
CPE		cpe:2.3:a:mongodb:c_driver::::::mongodb::*

08 Oct 2026, 19:16

Type	Values Removed	Values Added
New CVE

Information

Published : 2026-10-08 19:16

Updated : 2026-10-27 19:56

NVD link : CVE-2026-106437

Mitre link : CVE-2026-106437

CVE.ORG link : CVE-2026-106437

JSON object : View

Products Affected

mongodb

c_driver

CWE

CWE-191

Integer Underflow (Wrap or Wraparound)

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