---
id: CVE-2026-18709
title: >-
  An issue in MongoDB Server could allow an authenticated user with direct
  network access to a shard to improperly commit or abort an in-progress
  prepared transaction, bypassing the intended transaction coordination process
summary: >-
  An issue in MongoDB Server could allow an authenticated user with direct
  network access to a shard to improperly commit or abort an in-progress
  prepared transaction, bypassing the intended transaction coordination process.
  This could res…
severity: medium
cvss: 6.4
cvssVector: 'CVSS:3.1/AV:A/AC:H/PR:L/UI:N/S:U/C:N/I:H/A:H'
cwe:
  - CWE-862
vendor: mongodb
product: mongodb
affected:
  - 'mongodb >= 7.0.0, < 7.0.40'
  - 'mongodb >= 8.0.0, < 8.0.29'
  - 'mongodb >= 8.2.0, <= 8.2.12'
  - 'mongodb >= 8.3.0, < 8.3.8'
  - mongodb = 9.0.0
  - mongodb = 9.1.0
patched:
  - mongodb 8.3.8
published: '2026-08-11'
updated: '2026-09-16'
sourceUpdated: '2026-09-16T15:19:45.197'
source: NVD
sourceUrl: 'https://nvd.nist.gov/vuln/detail/CVE-2026-18709'
references:
  - url: 'https://jira.mongodb.org/browse/SERVER-130544'
    label: cna@mongodb.com
tags:
  - nvd
epss: 0.00131
epssPercentile: 0.03094
ingestedAt: '2026-08-29T19:41:16.244Z'
---

## Overview

An issue in MongoDB Server could allow an authenticated user with direct network access to a shard to improperly commit or abort an in-progress prepared transaction, bypassing the intended transaction coordination process. This could result in cross-shard data inconsistency, cluster clock corruption, and violation of transaction atomicity guarantees.

## Affected

- `mongodb >= 7.0.0, < 7.0.40`
- `mongodb >= 8.0.0, < 8.0.29`
- `mongodb >= 8.2.0, <= 8.2.12`
- `mongodb >= 8.3.0, < 8.3.8`
- `mongodb = 9.0.0`
- `mongodb = 9.1.0`

## Remediation

Upgrade past the affected range:

- `mongodb 8.3.8`