---
id: CVE-2026-88026
title: >-
  Improper neutralization of regular-expression metacharacters in the LINQ query
  translation component of the MongoDB C# Driver can cause a caller-supplied
  character sequence to alter a regular-expression predicate generated by an
  affected…
summary: >-
  Improper neutralization of regular-expression metacharacters in the LINQ query
  translation component of the MongoDB C# Driver can cause a caller-supplied
  character sequence to alter a regular-expression predicate generated by an
  affected…
severity: medium
cvss: 6.5
cvssVector: 'CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:N/A:N'
cwe:
  - CWE-943
vendor: mongodb
product: c#_driver
affected:
  - 'c#_driver >= 2.14.0, < 3.11.2'
patched:
  - c#_driver 3.11.2
published: '2026-09-10'
updated: '2026-09-29'
sourceUpdated: '2026-09-29T16:17:10.160'
source: NVD
sourceUrl: 'https://nvd.nist.gov/vuln/detail/CVE-2026-88026'
references:
  - url: 'https://jira.mongodb.org/browse/CSHARP-6177'
    label: cna@mongodb.com
tags:
  - nvd
  - cve.org
epss: 0.00379
epssPercentile: 0.31756
ssvc:
  exploitation: none
  automatable: 'no'
  technicalImpact: partial
  timestamp: '2026-09-10T18:23:15.544067Z'
ingestedAt: '2026-09-11T16:45:48.027Z'
---

## Overview

Improper neutralization of regular-expression metacharacters in the LINQ query translation component of the MongoDB C# Driver can cause a caller-supplied character sequence to alter a regular-expression predicate generated by an affected application. An authenticated user who can influence such a value may cause the application to return records beyond those intended by the original filter.

## Affected

- `c#_driver >= 2.14.0, < 3.11.2`

## Remediation

Upgrade past the affected range:

- `c#_driver 3.11.2`