CVE-2026-84965 — MEDIUM (5.1)

Vulnerability Description

An integer wraparound in an allocation size calculation in the BSON library's JSON parsing code can cause a buffer to be released while a following copy operation still writes through the stale pointer. On builds where sizes are 32 bits, an unauthenticated party able to supply a sufficiently large JSON input to an application that links the library may cause that application to terminate unexpectedly, resulting in denial of service.

CVSS Score

5.1

MEDIUM

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

Attack Vector

LOCAL

Attack Complexity

HIGH

Privileges Required

NONE

User Interaction

NONE

Scope

UNCHANGED

Confidentiality

NONE

Integrity

NONE

Availability

HIGH

Related Weaknesses (CWE)

CWE-190

References

https://jira.mongodb.org/browse/CDRIVER-6405

FAQ

What is CVE-2026-84965?

CVE-2026-84965 is a vulnerability with a CVSS score of 5.1 (MEDIUM). An integer wraparound in an allocation size calculation in the BSON library's JSON parsing code can cause a buffer to be released while a following copy operation still writes through the stale pointe...

How severe is CVE-2026-84965?

CVE-2026-84965 has been rated MEDIUM with a CVSS base score of 5.1/10. Review the CVSS metrics above for detailed severity breakdown.

Is there a patch for CVE-2026-84965?

Check the references section above for vendor advisories and patch information. Review vendor security bulletins for remediation guidance.