---
id: CVE-2026-93761
title: >-
  An inefficient regular expression complexity issue in the in-memory query
  evaluation component of the Mongoid library may allow an unauthenticated party
  to cause excessive processing within an embedding application process
summary: >-
  An inefficient regular expression complexity issue in the in-memory query
  evaluation component of the Mongoid library may allow an unauthenticated party
  to cause excessive processing within an embedding application process.
  Applications …
severity: high
cvss: 7.5
cvssVector: 'CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H'
cwe:
  - CWE-1333
vendor: mongodb
product: mongoid
affected:
  - 'mongoid >= 8.0.0, < 8.0.13'
  - 'mongoid >= 8.1.0, < 8.1.13'
  - 'mongoid >= 9.0.0, < 9.0.12'
  - mongoid = 9.1.0
patched:
  - mongoid 9.0.12
published: '2026-09-18'
updated: '2026-09-24'
sourceUpdated: '2026-09-24T16:06:04.550'
source: NVD
sourceUrl: 'https://nvd.nist.gov/vuln/detail/CVE-2026-93761'
references:
  - url: 'https://jira.mongodb.org/browse/MONGOID-5981'
    label: cna@mongodb.com
tags:
  - nvd
  - cve.org
epss: 0.0046
epssPercentile: 0.37233
ssvc:
  exploitation: none
  automatable: 'yes'
  technicalImpact: partial
  timestamp: '2026-09-19T13:43:12.765955Z'
ingestedAt: '2026-09-18T17:46:41.548Z'
---

## Overview

An inefficient regular expression complexity issue in the in-memory query evaluation component of the Mongoid library may allow an unauthenticated party to cause excessive processing within an embedding application process. Applications that place user-supplied text into a pattern-matching query condition on an embedded association may become unresponsive.

## Affected

- `mongoid >= 8.0.0, < 8.0.13`
- `mongoid >= 8.1.0, < 8.1.13`
- `mongoid >= 9.0.0, < 9.0.12`
- `mongoid = 9.1.0`

## Remediation

Upgrade past the affected range:

- `mongoid 9.0.12`