CVE-2026-43621

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 v3 8.1 HIGH

8.1^/10

CVSS v3 : HIGH

Vector :

Exploitability : 2.8 / Impact : 5.2

Attack Vector NETWORK

Attack Complexity LOW

Privileges Required LOW

User Interaction NONE

Confidentiality Impact HIGH

Integrity Impact HIGH

Availability Impact NONE

Scope UNCHANGED

References

Link	Resource
https://github.com/SimpleMachines/SMF/commit/6f0dc61958aa86a4b436a222f6176812ed5bbb95
https://www.vulncheck.com/advisories/simple-machines-forum-authorization-confusion-via-profile-load

Configurations

No configuration.

History

No history.

Information

Published : 2026-08-26 22:16

Updated : 2026-08-28 20:17

NVD link : CVE-2026-43621

Mitre link : CVE-2026-43621

CVE.ORG link : CVE-2026-43621

JSON object : View

Products Affected

No product.

CWE

CWE-863

Incorrect Authorization

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