CVE-2026-84965
Heap write primitive via size round-up wrap during JSON parsing on 32-bit builds
CVSS Score
5.1
EPSS Score
0.0%
EPSS Percentile
0th
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.
| CWE | CWE-190 |
| Vendor | mongodb |
| Product | c driver |
| Ecosystems | |
| Industries | Technology |
| Published | Sep 3, 2026 |
| Last Updated | Sep 3, 2026 |
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CVSS v3 Breakdown
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
Affected Versions
MongoDB / C Driver
1.10.0 < 1.30.9 2.0.0 < 2.5.2