CVE-2026-84966
An incorrect numeric type conversion in the BSON document building component of the MongoDB C++ Driver may cause a length value to be interpreted incorrectly. When an application supplies an extremely large, non-terminated field name to the builder, the library may read memory outside the intended buffer and terminate the calling process. No authentication is required, but the calling application must pass the oversized name in a specific form.
Published:Sep 3, 2026
Last Modified:Sep 3, 2026
EPS:Sep 3, 2026
EPSS Score:
CVSS Score:5.1
Affected Products
Vendor
Product
Action
Vendor
Mongodb
Product
C++ Driver
Mongodb
C++ Driver
Exploits
No exploit reference
Common Weakness Enumeration
Common Attack Pattern Enumeration and Classification (CAPEC)
No CAPEC recorded yet
References
Common Vulnerability Scoring System
Attack Vector
Network
Adjacent
Local
Physical
Privileges Required
None
Low
High
User Interaction
None
Required
Scope
Unchanged
Changed
Confidentiality
None
Low
High
Integrity
None
Low
High
Availability
None
Low
High
