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CVE-2026-84965 (GCVE-0-2026-84965)

Vulnerability from cvelistv5 – Published: 2026-09-03 15:01 – Updated: 2026-09-03 15:44
VLAI
Title
Heap write primitive via size round-up wrap during JSON parsing on 32-bit builds
Summary
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.
Severity
5.9 (Medium)
CVSS:4.0/AV:L/AC:H/AT:P/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N
5.1 (Medium)
CVSS:3.1/AV:L/AC:H/PR:N/UI:N/S:U/C:N/I:N/A:H
SSVC
Exploitation: none Automatable: no Technical Impact: partial
CISA Coordinator · CISA-ADP (v2.0.3)
Decision recorded 2026-09-03 15:43 UTC
CWE
  • CWE-190 - Integer Overflow or Wraparound
Assigner
References
Impacted products
Vendor Product Version CPE status
MongoDB C Driver Affected: 1.10.0 , < 1.30.9 (semver)
Affected: 2.0.0 , < 2.5.2 (semver)
guessed Create a notification for this product.
Show details on NVD website
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  • Seen: The vulnerability was mentioned, discussed, or observed by the user.
  • Confirmed: The vulnerability has been validated from an analyst's perspective.
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