{"id":"UBUNTU-CVE-2026-81521","details":"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.","modified":"2026-09-02T16:28:28Z","published":"2026-08-27T20:18:00Z","upstream":["CVE-2026-81521"],"references":[{"type":"REPORT","url":"https://ubuntu.com/security/CVE-2026-81521"},{"type":"REPORT","url":"https://www.cve.org/CVERecord?id=CVE-2026-81521"},{"type":"REPORT","url":"https://jira.mongodb.org/browse/GODRIVER-4075"},{"type":"REPORT","url":"https://pkg.go.dev/go.mongodb.org/mongo-driver/v2@v2.8.2"}],"affected":[{"package":{"name":"golang-mongodb-mongo-driver","ecosystem":"Ubuntu:24.04:LTS","purl":"pkg:deb/ubuntu/golang-mongodb-mongo-driver?arch=source&distro=noble"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"}]}],"versions":["1.8.4+ds1-1ubuntu1","1.12.1+ds1-2"],"ecosystem_specific":{"binaries":[{"binary_name":"golang-mongodb-mongo-driver-dev","binary_version":"1.12.1+ds1-2"}]},"database_specific":{"source":"https://github.com/canonical/ubuntu-security-notices/blob/main/osv/cve/2026/UBUNTU-CVE-2026-81521.json"}},{"package":{"name":"golang-mongodb-mongo-driver","ecosystem":"Ubuntu:26.04:LTS","purl":"pkg:deb/ubuntu/golang-mongodb-mongo-driver?arch=source&distro=resolute"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"}]}],"versions":["1.17.1+ds1-2"],"ecosystem_specific":{"binaries":[{"binary_name":"golang-mongodb-mongo-driver-dev","binary_version":"1.17.1+ds1-2"}]},"database_specific":{"source":"https://github.com/canonical/ubuntu-security-notices/blob/main/osv/cve/2026/UBUNTU-CVE-2026-81521.json"}}],"schema_version":"1.9.0","severity":[{"type":"CVSS_V3","score":"CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:H/A:N"},{"type":"CVSS_V4","score":"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"},{"type":"Ubuntu","score":"medium"}]}