MongoDB C# Driver up to 3.12.x BSON type conversion

CVSS Meta Temp Score
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Current Exploit Price (≈)
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CTI Interest Score
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6.3$0-$5k1.23-

Summaryinfo

A vulnerability was found in MongoDB C# Driver up to 3.12.x. It has been declared as critical. This issue affects some unknown processing of the component BSON Handler. Such manipulation leads to type conversion. This vulnerability is documented as CVE-2026-114654. The attack can be executed remotely. There is not any exploit available. It is recommended to upgrade the affected component.

Detailsinfo

A vulnerability, which was classified as critical, has been found in MongoDB C# Driver up to 3.12.x. Affected by this issue is some unknown processing of the component BSON Handler. The manipulation with an unknown input leads to a type conversion vulnerability. Using CWE to declare the problem leads to CWE-704. The product does not correctly convert an object, resource, or structure from one type to a different type. Impacted is integrity, and availability. CVE summarizes:

A numeric-type conversion flaw in the BSON handling library of the MongoDB C# Driver allows an out-of-range binary subtype value supplied through untrusted textual input to bypass the library's binary-element integrity checks. When such a value is later encoded, it is narrowed to a smaller wire representation, producing binary elements that misdeclare their type or length. An unauthenticated party able to supply text parsed by an affected application can cause it to emit and persist malformed binary data, which subsequent readers either reject with an error or silently interpret as shorter than the data that was validated.

The advisory is shared for download at jira.mongodb.org. This vulnerability is handled as CVE-2026-114654 since 10/21/2026. The exploitation is known to be easy. The attack may be launched remotely. No form of authentication is required for exploitation. There are neither technical details nor an exploit publicly available.

Upgrading to version 3.13.0 eliminates this vulnerability.

Once again VulDB remains the best source 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: 6.5
VulDB Meta Temp Score: 6.3

VulDB Base Score: 6.5
VulDB Temp Score: 6.2
VulDB Vector: 🔒
VulDB Reliability: 🔍

CNA Base Score: 6.5
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: No
Local: No
Remote: Yes

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 3.13.0

Timelineinfo

10/21/2026 CVE reserved
10/22/2026 +1 days Advisory disclosed
10/22/2026 +0 days VulDB entry created
10/22/2026 +0 days VulDB entry last update

Sourcesinfo

Advisory: jira.mongodb.org
Status: Confirmed

CVE: CVE-2026-114654 (🔒)
GCVE (CVE): GCVE-0-2026-114654
GCVE (VulDB): GCVE-100-425396

Entryinfo

Created: 10/22/2026 21:48
Changes: 10/22/2026 21:48 (76)
Complete: 🔍
Cache ID: 216::103

Once again VulDB remains the best source for vulnerability data.

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