---
id: CVE-2026-76821
title: >-
  OpenCTI is an open source platform for managing cyber threat intelligence
  knowledge and observables
summary: >-
  OpenCTI is an open source platform for managing cyber threat intelligence
  knowledge and observables. Prior to 7.260706.0, the JSON ingestion mapper's
  extractWithRegexp formula function compiled a user-supplied regular expression
  with the…
severity: high
cvss: 7.1
cvssVector: 'CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N'
cwe:
  - CWE-400
  - CWE-1333
vendor: OpenCTI-Platform
product: opencti
affected:
  - opencti < 7.260706.0
published: '2026-09-15'
updated: '2026-09-16'
sourceUpdated: '2026-09-16T19:17:34.207'
source: NVD
sourceUrl: 'https://nvd.nist.gov/vuln/detail/CVE-2026-76821'
references:
  - url: >-
      https://github.com/OpenCTI-Platform/opencti/commit/3d726c09480f96980ce4c3e6119a8034dbdf2c96
    label: security-advisories@github.com
  - url: 'https://github.com/OpenCTI-Platform/opencti/pull/16935'
    label: security-advisories@github.com
  - url: 'https://github.com/OpenCTI-Platform/opencti/releases/tag/7.260706.0'
    label: security-advisories@github.com
  - url: >-
      https://github.com/OpenCTI-Platform/opencti/security/advisories/GHSA-7g3x-wc2m-9h9x
    label: security-advisories@github.com
tags:
  - nvd
  - cve.org
ssvc:
  exploitation: none
  automatable: 'no'
  technicalImpact: partial
  timestamp: '2026-09-16T18:18:34.960509Z'
cvssSource: cna
ingestedAt: '2026-09-15T19:42:58.813Z'
epss: 0.00466
epssPercentile: 0.37695
---

## Overview

OpenCTI is an open source platform for managing cyber threat intelligence knowledge and observables. Prior to 7.260706.0, the JSON ingestion mapper's extractWithRegexp formula function compiled a user-supplied regular expression with the JavaScript RegExp engine in opencti-platform/opencti-graphql/src/parser/json-mapper.ts without validating its complexity. An authenticated user with JSON mapper creation permission could provide a catastrophically backtracking pattern and matching ingestion input, blocking the Node.js event loop and making the GraphQL API unavailable to all users. Scheduled ingestion could repeatedly execute the malicious mapper without additional attacker action, and recovery could require disabling the mapper and restarting the process. The issue affects availability and does not expose or modify data. This issue is fixed in version 7.260706.0.

## Remediation

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