MongoDB C++ Driver up to 4.5.1 BSON Document Building type conversion

CVSS Meta Temp Score
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Current Exploit Price (≈)
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CTI Interest Score
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5.1$0-$5k1.38+

Summaryinfo

A vulnerability described as problematic has been identified in MongoDB C++ Driver up to 4.5.1. This affects an unknown part of the component BSON Document Building. The manipulation results in type conversion. This vulnerability is identified as CVE-2026-84966. The attack is only possible with local access. There is not any exploit available.

Detailsinfo

A vulnerability classified as problematic has been found in MongoDB C++ Driver up to 4.5.1. Affected is an unknown code block of the component BSON Document Building. The manipulation with an unknown input leads to a type conversion vulnerability. CWE is classifying the issue as CWE-704. The product does not correctly convert an object, resource, or structure from one type to a different type. This is going to have an impact on confidentiality, integrity, and availability. CVE summarizes:

An incorrect numeric type conversion in the BSON document building component of the MongoDB C++ Driver may cause a length value to be interpreted incorrectly. When an application supplies an extremely large, non-terminated field name to the builder, the library may read memory outside the intended buffer and terminate the calling process. No authentication is required, but the calling application must pass the oversized name in a specific form.

The advisory is available at jira.mongodb.org. This vulnerability is traded as CVE-2026-84966 since 09/02/2026. The exploitability is told to be easy. Local access is required to approach this attack. The technical details are unknown and an exploit is not available.

Upgrading to version 4.5.2 eliminates this vulnerability.

If you want to get best quality of vulnerability data, you may have to visit VulDB.

Productinfo

Type

Vendor

Name

Version

License

CPE 2.3info

CPE 2.2info

CVSSv4info

VulDB Vector: 🔒
VulDB Reliability: 🔍

CNA CVSS-B Score: 🔒
CNA CVSS-BT Score: 🔒
CNA Vector: 🔒

CVSSv3info

VulDB Meta Base Score: 5.2
VulDB Meta Temp Score: 5.1

VulDB Base Score: 5.3
VulDB Temp Score: 5.1
VulDB Vector: 🔒
VulDB Reliability: 🔍

CNA Base Score: 5.1
CNA Vector (mongodb): 🔒

CVSSv2info

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VectorComplexityAuthenticationConfidentialityIntegrityAvailability
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VulDB Base Score: 🔒
VulDB Temp Score: 🔒
VulDB Reliability: 🔍

Exploitinginfo

Class: Type conversion
CWE: CWE-704
CAPEC: 🔒
ATT&CK: 🔒

Physical: Partially
Local: Yes
Remote: No

Availability: 🔒
Status: Not defined
Price Prediction: 🔍
Current Price Estimation: 🔒

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Threat Intelligenceinfo

Interest: 🔍
Active Actors: 🔍
Active APT Groups: 🔍

Countermeasuresinfo

Recommended: Upgrade
Status: 🔍

0-Day Time: 🔒

Upgrade: C++ Driver 4.5.2

Timelineinfo

09/02/2026 CVE reserved
09/03/2026 +1 days Advisory disclosed
09/03/2026 +0 days VulDB entry created
09/03/2026 +0 days VulDB entry last update

Sourcesinfo

Advisory: jira.mongodb.org
Status: Confirmed

CVE: CVE-2026-84966 (🔒)
GCVE (CVE): GCVE-0-2026-84966
GCVE (VulDB): GCVE-100-398466

Entryinfo

Created: 09/03/2026 17:44
Changes: 09/03/2026 17:44 (76)
Complete: 🔍
Cache ID: 216::103

If you want to get best quality of vulnerability data, you may have to visit VulDB.

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