CVE-2026-84970
Low
No strong exploitation signal.
CVSS base
6.2
MEDIUM
CVSS:3.1/AV:L/AC:H/PR:N/UI:N/S:U/C:L/I:L/A:H
EPSS — probability of exploitation (30 days)
0.1%
0.5th percentile
CISA KEV
Not listed
Weakness / dates
CWE-681
Published 2026-09-03 · modified 2026-09-10
CVSS breakdown
CVSS:3.1/AV:L/AC:H/PR:N/UI:N/S:U/C:L/I:L/A:H
| Attack Vector | L | Local |
| Attack Complexity | H | High |
| Privileges Required | N | None |
| User Interaction | N | None |
| Scope | U | Unchanged |
| Confidentiality | L | Low |
| Integrity | L | Low |
| Availability | H | High |
Timeline
- 2026-09-03 — Published (NVD)
- 2026-09-10 — Last modified (NVD)
Description
A numeric truncation weakness exists in the JSON parsing component of the MongoDB C++ Driver's BSON library. An actor who controls the text that an embedding application hands to the library's public JSON parsing interface, when that text is very large, can cause the library to read memory beyond the supplied buffer and return it to the caller, to silently accept only part of the input as a complete document, or to terminate the process. No MongoDB server, credentials, or non-default configuration is required; the effect is confined to the process that uses the library.