---
id: CVE-2026-43621
title: >-
  Simple Machines Forum (SMF) through 2.1.7, fixed in commit 6f0dc61, contains
  an authorization state-confusion vulnerability in the profile loader that
  allows authenticated low-privileged users to gain administrator access by
  supplying mu…
summary: >-
  Simple Machines Forum (SMF) through 2.1.7, fixed in commit 6f0dc61, contains
  an authorization state-confusion vulnerability in the profile loader that
  allows authenticated low-privileged users to gain administrator access by
  supplying mu…
severity: high
cvss: 8.1
cvssVector: 'CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:N'
cwe:
  - CWE-863
published: '2026-08-26'
updated: '2026-09-24'
sourceUpdated: '2026-09-24T20:28:01.780'
source: NVD
sourceUrl: 'https://nvd.nist.gov/vuln/detail/CVE-2026-43621'
references:
  - url: >-
      https://github.com/SimpleMachines/SMF/commit/6f0dc61958aa86a4b436a222f6176812ed5bbb95
    label: disclosure@vulncheck.com
  - url: >-
      https://www.vulncheck.com/advisories/simple-machines-forum-authorization-confusion-via-profile-load
    label: disclosure@vulncheck.com
tags:
  - nvd
epss: 0.00363
epssPercentile: 0.27491
ingestedAt: '2026-09-24T20:51:40.233Z'
---

## Overview

Simple Machines Forum (SMF) through 2.1.7, fixed in commit 6f0dc61, contains an authorization state-confusion vulnerability in the profile loader that allows authenticated low-privileged users to gain administrator access by supplying multiple values for the user parameter. Attackers can exploit the mismatch between Profile::$member and User::$me->is_owner during sequential profile loading to be treated as the owner of an administrator profile, enabling unauthorized password changes and full account takeover.

## Remediation

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