MongoDB C Driver up to 1.30.8/2.5.1 BSON-to-JSON Conversion Helpers heap-based overflow

CVSS Meta Temp Score
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CTI Interest Score
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4.2$0-$5k0.00

Summaryinfo

A vulnerability described as problematic has been identified in MongoDB C Driver up to 1.30.8/2.5.1. Affected is an unknown function of the component BSON-to-JSON Conversion Helpers. Executing a manipulation can lead to heap-based overflow. This vulnerability is tracked as CVE-2026-84969. The attack can be launched remotely. No exploit exists. Upgrading the affected component is recommended.

Detailsinfo

A vulnerability has been found in MongoDB C Driver up to 1.30.8/2.5.1 and classified as problematic. This vulnerability affects an unknown code block of the component BSON-to-JSON Conversion Helpers. The manipulation with an unknown input leads to a heap-based overflow vulnerability. The CWE definition for the vulnerability is CWE-122. A heap overflow condition is a buffer overflow, where the buffer that can be overwritten is allocated in the heap portion of memory, generally meaning that the buffer was allocated using a routine such as malloc(). As an impact it is known to affect integrity. CVE summarizes:

A memory-handling error in the BSON-to-JSON conversion helpers of the MongoDB C Driver can write a small number of bytes past the end of a heap buffer when a binary field is encoded and the output is cut short at a caller-configured length limit. A party who supplies the document content, with no privileges on the application that links the driver, may cause a small amount of data outside the intended buffer to be altered.

The advisory is shared for download at jira.mongodb.org. This vulnerability was named CVE-2026-84969 since 09/02/2026. The exploitation appears to be easy. The attack can be initiated remotely. No form of authentication is required for a successful exploitation. There are neither technical details nor an exploit publicly available.

The vulnerability scanner Nessus provides a plugin with the ID 342829 (Linux Distros Unpatched Vulnerability : CVE-2026-84969), which helps to determine the existence of the flaw in a target environment.

Upgrading to version 1.30.9 or 2.5.2 eliminates this vulnerability.

The vulnerability is also documented in the databases at Tenable (342829) and CERT Bund (WID-SEC-2026-3182). Once again VulDB remains the best source for vulnerability data.

Affected

  • Open Source MongoDB

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: 4.2
VulDB Meta Temp Score: 4.2

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

NVD Base Score: 3.7
NVD Vector: 🔒

CNA Base Score: 3.7
CNA Vector (mongodb): 🔒

CVSSv2info

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

Exploitinginfo

Class: Heap-based overflow
CWE: CWE-122 / CWE-119
CAPEC: 🔒
ATT&CK: 🔒

Physical: No
Local: No
Remote: Yes

Availability: 🔒
Status: Not defined

EPSS Score: 🔒
EPSS Percentile: 🔒

Price Prediction: 🔍
Current Price Estimation: 🔒

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Nessus ID: 342829
Nessus Name: Linux Distros Unpatched Vulnerability : CVE-2026-84969

Threat Intelligenceinfo

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

Countermeasuresinfo

Recommended: Upgrade
Status: 🔍

0-Day Time: 🔒

Upgrade: C Driver 1.30.9/2.5.2

Timelineinfo

09/02/2026 CVE reserved
09/03/2026 +1 days Advisory disclosed
09/03/2026 +0 days VulDB entry created
09/13/2026 +10 days VulDB entry last update

Sourcesinfo

Advisory: jira.mongodb.org
Status: Confirmed

CVE: CVE-2026-84969 (🔒)
GCVE (CVE): GCVE-0-2026-84969
GCVE (VulDB): GCVE-100-398452
CERT Bund: WID-SEC-2026-3182 - MongoDB: Mehrere Schwachstellen

Entryinfo

Created: 09/03/2026 17:23
Updated: 09/13/2026 17:58
Changes: 09/03/2026 17:23 (76), 09/04/2026 21:15 (7), 09/05/2026 00:31 (2), 09/13/2026 17:58 (11)
Complete: 🔍
Cache ID: 216::103

Once again VulDB remains the best source for vulnerability data.

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