CVE-2026-96749 (GCVE-0-2026-96749)

Vulnerability from cvelistv5 – Published: 2026-09-24 18:18 – Updated: 2026-09-26 03:55
VLAI
Title
Heap out-of-bounds write via signed size overflow in BSON document encoding
Summary
An integer overflow in the BSON document encoding component of the MongoDB Python Driver's bundled native extension may occur when a single document is built from an unusually large amount of caller-supplied data. Size arithmetic is performed in a signed 32-bit type, and the guard meant to catch the overflow is written in a form whose behavior is not defined by the C language standard. A party with no privileges who can place a very large value into data that an application encodes may, depending on how the native extension was built, cause a write outside the bounds of an allocated buffer inside the application's own process.
Severity
7.5 (High)
CVSS:4.0/AV:L/AC:L/AT:P/PR:N/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N
8.4 (High)
CVSS:3.1/AV:L/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
SSVC
Exploitation: none Automatable: no Technical Impact: total
CISA Coordinator · CISA-ADP (v2.0.3)
Decision recorded 2026-09-25 00:00 UTC
CWE
  • CWE-190 - Integer Overflow or Wraparound
Assigner
mongodb CNA under the mitre root
CNA scorecard C 70/100 over 204 records in the last 180 days details
References
Impacted products
Vendor Product Version CPE status
MongoDB Python Driver Affected: 1.9.0 , < 4.18.2 (semver)
guessed Create a notification for this product.
Show details on NVD website
To clipboard 

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