Vulnerability in MongoDB Go Driver
CVE-2026-81521
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.
Published · last modified .
CVSS v3 metric
CVSS v3 base score 6.5 (Medium). Vector: CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:H/A:N.
EPSS exploit prediction
EPSS: 0.002 (10.0th percentile), scored .
Very low probability of exploitation in the next 30 days; routine patching cadence is appropriate. 10th percentile — 10.0% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.
EPSS over last 30 days · oldest: 0.002 · newest: 0.002 · change: +0.000
Affected products
Weakness classification (CWE)
References
- pkg.go.dev/go.mongodb.org/mongo-driver/v2@v2.8.2 (Product)
- jira.mongodb.org/browse/GODRIVER-4075 (Vendor Advisory)
Frequently asked questions
- What is CVE-2026-81521?
- CVE-2026-81521 is a medium-severity vulnerability in MongoDB Go Driver, classified under Resource Injection. CVSS score: 6.5/10. Published 2026-08-27.
- How severe is CVE-2026-81521?
- Medium severity. CVSS v3 base score is 6.5 out of 10.