CVE-2026-43621: Incorrect Authorization in SimpleMachines SMF
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.
CVE-2026-43621: Incorrect Authorization in SimpleMachines SMF
Description
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.
CVSS v4.0
Score 8.6high
Affected software
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Technical Details
- Data Version
- 5.2
- Assigner Short Name
- VulnCheck
- Date Reserved
- 2026-05-01T18:22:45.640Z
- Cvss Version
- 4.0
- State
- PUBLISHED
- Remediation Level
- null
Threat ID: 6a8f63b0acd9273b4970b50a
Added to database: 08/26/2026, 22:07:44 UTC
Last updated: 08/27/2026, 03:37:03 UTC
Views: 8
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