---
id: CVE-2026-96749
title: >-
  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
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 perf…
severity: high
cvss: 8.4
cvssVector: 'CVSS:3.1/AV:L/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H'
cwe:
  - CWE-190
  - CWE-787
vendor: MongoDB
product: Python Driver
affected:
  - python_driver >= 1.9.0 < 4.18.2
published: '2026-09-24'
updated: '2026-09-26'
sourceUpdated: '2026-09-26T04:17:52.260'
source: NVD
sourceUrl: 'https://nvd.nist.gov/vuln/detail/CVE-2026-96749'
references:
  - url: >-
      https://github.com/mongodb/mongo-python-driver/blob/4.18.2/doc/changelog.rst
    label: cna@mongodb.com
  - url: 'https://github.com/mongodb/mongo-python-driver/releases/tag/4.18.2'
    label: cna@mongodb.com
  - url: >-
      https://github.com/mongodb/mongo-python-driver/security/advisories/GHSA-v4x9-3549-crwv
    label: cna@mongodb.com
  - url: >-
      https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-96749.json
  - url: 'https://access.redhat.com/security/cve/CVE-2026-96749'
  - url: 'https://bugzilla.redhat.com/show_bug.cgi?id=2540688'
  - url: 'https://www.cve.org/CVERecord?id=CVE-2026-96749'
  - url: 'https://nvd.nist.gov/vuln/detail/CVE-2026-96749'
tags:
  - nvd
  - cve.org
  - csaf
  - vex
  - red-hat
ssvc:
  exploitation: none
  automatable: 'no'
  technicalImpact: total
  timestamp: '2026-09-25T00:00:00+00:00'
epss: 0.00132
epssPercentile: 0.02283
ingestedAt: '2026-09-24T18:49:36.719Z'
---

## Overview

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.

## Remediation

Refer to the linked advisories for vendor-supplied fixes and affected version ranges.

## Vendor advisories

- **Red Hat VEX** · Important · affected: Red Hat OpenShift AI (RHOAI), Red Hat OpenStack Platform 13 (Queens), Red Hat OpenStack Platform 16.2, Red Hat OpenStack Platform 17.1 · no fix planned: Red Hat OpenShift AI (RHOAI), Red Hat OpenStack Platform 13 (Queens), Red Hat OpenStack Platform 16.2, Red Hat OpenStack Platform 17.1 · updated 2026-09-24 · [vex](https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-96749.json)