---
id: CVE-2026-95671
title: >-
  In MISP, the CollectionsController add() method enforced the sharing-group
  usability authorization check and element capture only when the HTTP request
  method was POST
summary: >-
  In MISP, the CollectionsController add() method enforced the sharing-group
  usability authorization check and element capture only when the HTTP request
  method was POST. However, the underlying CRUDComponent::add() method persists
  data on…
severity: medium
cvss: 5.3
cvssVector: 'CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:N/VI:L/VA:N/SC:N/SI:L/SA:N'
cwe:
  - CWE-285
  - CWE-862
vendor: MISP
product: MISP
affected:
  - MISP < 2.5.47
published: '2026-09-22'
updated: '2026-09-22'
sourceUpdated: '2026-09-22T16:18:22.057'
source: NVD
sourceUrl: 'https://nvd.nist.gov/vuln/detail/CVE-2026-95671'
references:
  - url: 'https://github.com/MISP/MISP/commit/c20f5a836'
    label: 5a6e4751-2f3f-4070-9419-94fb35b644e8
tags:
  - nvd
  - cve.org
ssvc:
  exploitation: none
  automatable: 'no'
  technicalImpact: partial
  timestamp: '2026-09-22T15:32:15.165861Z'
cvssSource: cna
ingestedAt: '2026-09-22T14:04:19.591Z'
epss: 0.00372
epssPercentile: 0.31113
---

## Overview

In MISP, the CollectionsController add() method enforced the sharing-group usability authorization check and element capture only when the HTTP request method was POST. However, the underlying CRUDComponent::add() method persists data on both POST and PUT requests. As a result, an authenticated user could issue a PUT request to the collections/add endpoint, bypassing the sharing-group authorization check entirely. This allowed the creation of a collection with distribution=4 (shared with a specific sharing group) targeting a sharing group that the user was not authorized to use. The bypassed check would normally verify that the current user has access to the specified sharing group before allowing the collection to be associated with it.

The security impact is that an authenticated user can place collection data into a sharing group context they do not have legitimate access to, potentially exposing that data to all members of the unauthorized sharing group and violating the intended access-control boundaries of the MISP instance.

The vulnerability requires an authenticated session and knowledge of a valid sharing group identifier; no user interaction or special tooling is needed beyond sending a PUT request instead of a POST request to the same endpoint.

## Remediation

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