CVE-2026-81521 HIGH

CVE-2026-81521: Cross-database write retargeting via unvalidated dotted database name in Client.BulkWrite in the MongoDB Go Driver

Vendor Mongodb
Product GO Driver
Weakness CWE-99
Published August 27, 2026
Last update August 28, 2026
View on NVD All CVEs

CVSS base score

7.1/10
Attack vector Network
Attack complexity Low
Privileges required Low
User interaction None
Confidentiality —
Integrity —

CVSS vector

CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:N/VI:H/VA:N/SC:N/SI:N/SA:N

What the vulnerability does

01Description

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.

Key dates

02Disclosure timeline

August 27, 2026 CVE published
August 28, 2026 Record updated