CVE-2026-84965

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 v3 5.1 MEDIUM

5.1^/10

CVSS v3 : MEDIUM

Vector :

Exploitability : 1.4 / Impact : 3.6

Attack Vector LOCAL

Attack Complexity HIGH

Privileges Required NONE

User Interaction NONE

Confidentiality Impact NONE

Integrity Impact NONE

Availability Impact HIGH

Scope UNCHANGED

References

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

Configurations

No configuration.

History

No history.

Information

Published : 2026-09-03 16:18

Updated : 2026-09-03 16:25

NVD link : CVE-2026-84965

Mitre link : CVE-2026-84965

CVE.ORG link : CVE-2026-84965

JSON object : View

Products Affected

No product.

CWE

CWE-190

Integer Overflow or Wraparound

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