MongoDB Go Driver up to 2.8.1 Bulk Write Operation Client.BulkWrite database name input validation

CVSS Meta Temp Score
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Current Exploit Price (≈)
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CTI Interest Score
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5.3$0-$5k0.64+

Summaryinfo

A vulnerability, which was classified as problematic, was found in MongoDB Go Driver up to 2.8.1. This issue affects the function Client.BulkWrite of the component Bulk Write Operation. Such manipulation of the argument database name leads to input validation. This vulnerability is documented as CVE-2026-81521. The attack can be executed remotely. There is not any exploit available.

Detailsinfo

A vulnerability was found in MongoDB Go Driver up to 2.8.1 and classified as problematic. Affected by this issue is the function Client.BulkWrite of the component Bulk Write Operation. The manipulation of the argument database name with an unknown input leads to a input validation vulnerability. Using CWE to declare the problem leads to CWE-20. The product receives input or data, but it does not validate or incorrectly validates that the input has the properties that are required to process the data safely and correctly. Impacted is integrity. CVE summarizes:

The MongoDB Go Driver's client-level bulk write operation may accept a caller-supplied database name containing a reserved separator character without escaping it before the name is used to build the target namespace for the operation. An application that passes untrusted input as a database name could therefore have the write directed at a database and collection other than the ones it intended. Only the Client.BulkWrite API is affected.

The advisory is shared for download at jira.mongodb.org. This vulnerability is handled as CVE-2026-81521 since 08/27/2026. The exploitation is known to be easy. The attack may be launched remotely. There are known technical details, but no exploit is available.

Upgrading to version 2.8.2 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: 5.4
VulDB Meta Temp Score: 5.3

VulDB Base Score: 4.3
VulDB Temp Score: 4.1
VulDB Vector: 🔒
VulDB Reliability: 🔍

CNA Base Score: 6.5
CNA Vector (mongodb): 🔒

CVSSv2info

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

Exploitinginfo

Class: Input validation
CWE: CWE-20
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: Go Driver 2.8.2

Timelineinfo

08/27/2026 Advisory disclosed
08/27/2026 +0 days CVE reserved
08/27/2026 +0 days VulDB entry created
08/27/2026 +0 days VulDB entry last update

Sourcesinfo

Advisory: jira.mongodb.org
Status: Confirmed

CVE: CVE-2026-81521 (🔒)
GCVE (CVE): GCVE-0-2026-81521
GCVE (VulDB): GCVE-100-396356

Entryinfo

Created: 08/27/2026 22:47
Changes: 08/27/2026 22:47 (78)
Complete: 🔍
Cache ID: 216::103

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