Vulnerability record · CVE-2026-81521 · published 27 August 2026
CVE-2026-81521: The MongoDB Go Driver's client-level bulk write operation may accept a caller-supplied database name containin…
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.
Description
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.
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/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:
References
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Source: NIST National Vulnerability Database (record CVE-2026-81521), CISA KEV, FIRST EPSS (scores of 2026-09-26). This page is refreshed as NVD updates the record.
