CVE-2026-84966

Publication date 4 September 2026

Last updated 4 September 2026


Ubuntu priority

Cvss 3 Severity Score

5.1 · Medium

Score breakdown

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.

Status

Package Ubuntu Release Status
mongo-cxx-driver 26.04 LTS resolute Not in release
24.04 LTS noble Not in release
22.04 LTS jammy Not in release

Severity score breakdown

CVSS version:

Base score 5.9 · Medium

Vector: 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

Base score 5.1 · Medium

Vector: CVSS:3.1/AV:L/AC:H/PR:N/UI:N/S:U/C:N/I:N/A:H


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