CVE-2026-84966
BSON element injection via NUL-embedded document keys in builder append
- State
- Published
- Severity
- 5.9 Medium
- Published
- Sep 3, 2026
- Updated
- Sep 3, 2026
- Reserved
- Sep 2, 2026
Description
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.
Scores
| CVSS | Score | Vector | Source |
|---|---|---|---|
| 4.0 | 5.9 Medium | CVSS:4.0/AV:L/AC:L/AT:P/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N | mongodb |
| 3.1 | 5.1 Medium | CVSS:3.1/AV:L/AC:H/PR:N/UI:N/S:U/C:N/I:N/A:H | mongodb |
Weaknesses
- CWE-681 Incorrect Conversion between Numeric Types
Affected Products
| Product | Versions |
|---|---|
C++ DriverMongoDB |
|
References
Every record here comes from the CVE Program’s CVE List. © 1999–2026 The MITRE Corporation. CVE is a registered trademark of The MITRE Corporation. The records are reproduced under the CVE Program terms of use.