CVE-2026-84966
BSON element injection via NUL-embedded document keys in builder append
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.
No summary for this CVE yet.
CVSS Vector Breakdown
Exploitability
AV:LAttack VectorLocal
AC:HAttack ComplexityHigh
PR:NPrivileges RequiredNone
UI:NUser InteractionNone
Scope
S:UScopeUnchanged
Impact
C:NConfidentialityNone
I:NIntegrityNone
A:HAvailabilityHigh
Weaknesses
Affected Products
MongoDB
commercial·US
C++ DriverOn-prem
Databases / nosqlExploitability
Official Patch Available
References
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