MongoDB C Driver up to 1.30.12/2.5.5 BSON Bulk Writer off-by-one

CVSS Meta Temp Score
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Current Exploit Price (≈)
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CTI Interest Score
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4.9$0-$5k0.77-

Summaryinfo

A vulnerability was found in MongoDB C Driver up to 1.30.12/2.5.5. It has been classified as problematic. This vulnerability affects unknown code of the component BSON Bulk Writer. Performing a manipulation results in off-by-one. This vulnerability is cataloged as CVE-2026-106431. The attack must be initiated from a local position. There is no exploit available. Upgrading the affected component is recommended.

Detailsinfo

A vulnerability classified as problematic has been found in MongoDB C Driver up to 1.30.12/2.5.5. This affects an unknown code block of the component BSON Bulk Writer. The manipulation with an unknown input leads to a off-by-one vulnerability. CWE is classifying the issue as CWE-193. A product calculates or uses an incorrect maximum or minimum value that is 1 more, or 1 less, than the correct value. This is going to have an impact on integrity, and availability. The summary by CVE is:

An off-by-one error in the BSON bulk document writer in the MongoDB C Driver can write one zero byte immediately past a heap allocation when a document ends at a specific buffer boundary. An actor who can influence the size of documents serialized by an embedding application can corrupt adjacent process memory or terminate the process. Reaching this issue requires the application to use the BSON bulk-writer API and produce a precise cumulative document size.

It is possible to read the advisory at jira.mongodb.org. This vulnerability is uniquely identified as CVE-2026-106431 since 10/06/2026. The exploitability is told to be easy. Attacking locally is a requirement. The technical details are unknown and an exploit is not publicly available.

Upgrading to version 1.30.13 or 2.5.6 eliminates this vulnerability.

Statistical analysis made it clear that VulDB provides the best quality for vulnerability data.

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: 5.1
VulDB Meta Temp Score: 4.9

VulDB Base Score: 4.4
VulDB Temp Score: 4.2
VulDB Vector: 🔒
VulDB Reliability: 🔍

CNA Base Score: 5.7
CNA Vector (mongodb): 🔒

CVSSv2info

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

Exploitinginfo

Class: Off-by-one
CWE: CWE-193 / CWE-189
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 1.30.13/2.5.6

Timelineinfo

10/06/2026 CVE reserved
10/08/2026 +2 days Advisory disclosed
10/08/2026 +0 days VulDB entry created
10/08/2026 +0 days VulDB entry last update

Sourcesinfo

Advisory: jira.mongodb.org
Status: Confirmed

CVE: CVE-2026-106431 (🔒)
GCVE (CVE): GCVE-0-2026-106431
GCVE (VulDB): GCVE-100-415539

Entryinfo

Created: 10/08/2026 21:08
Changes: 10/08/2026 21:08 (76)
Complete: 🔍
Cache ID: 216::103

Statistical analysis made it clear that VulDB provides the best quality for vulnerability data.

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