CVE-2026-93395

A missing lower-bound validation in the bson_new_from_buffer() function of libbson allows an integer underflow when processing BSON data with a zero-length prefix. The function reads a 32-bit document length from the input buffer but does not verify that the value is at least 5 (the minimum valid BSON document size) before using it in an array index calculation. When the length field is zero, the expression used to check the document's null terminator wraps to UINT32_MAX, causing a heap out-of-bounds read that crashes the process. An unauthorized party who can supply crafted BSON input to an application using this API can cause a denial of service.

CVSS v3 5.3 MEDIUM

5.3^/10

CVSS v3 : MEDIUM

Vector :

Exploitability : 3.9 / Impact : 1.4

Attack Vector NETWORK

Attack Complexity LOW

Privileges Required NONE

User Interaction NONE

Confidentiality Impact NONE

Integrity Impact NONE

Availability Impact LOW

Scope UNCHANGED

References

Link	Resource
https://jira.mongodb.org/browse/CDRIVER-6343	Permissions Required

Configurations

Configuration 1 (hide)

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

History

25 Sep 2026, 20:32

Type	Values Removed	Values Added
CPE		cpe:2.3:a:mongodb:c_driver::::::mongodb::*
First Time		Mongodb c Driver Mongodb
References	~~() https://jira.mongodb.org/browse/CDRIVER-6343 -~~	() https://jira.mongodb.org/browse/CDRIVER-6343 - Permissions Required

17 Sep 2026, 21:17

Type	Values Removed	Values Added
New CVE

Information

Published : 2026-09-17 21:17

Updated : 2026-09-25 20:32

NVD link : CVE-2026-93395

Mitre link : CVE-2026-93395

CVE.ORG link : CVE-2026-93395

JSON object : View

Products Affected

mongodb

c_driver

CWE

CWE-191

Integer Underflow (Wrap or Wraparound)

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