CVE-2026-84966 — BSON element injection via NUL-embedded document keys in builder append
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 applicatio…
Published: 2026-09-03 · CVSS: 5.9 · CVSS 4.0
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.
Source: CVE Program · Revision 8b16575c39f1e1810c5e863010da073d2d3285e7