CVE-2026-39903Simple Machines Forum 2.1 prior to commit 7d048f8 and 3.0 prior to commit a7875e8 contains an authorization bypass vulnerability in Sources/Actions/AttachmentApprove.php where a single-character oper…
Updated under an hour ago ()
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Simple Machines Forum 2.1 prior to commit 7d048f8 and 3.0 prior to commit a7875e8 contains an authorization bypass vulnerability in Sources/Actions/AttachmentApprove.php where a single-character operator error causes the permission check to always pass regardless of user permissions. An authenticated low-privileged user can approve, reject, or delete any pending attachments on any board without holding the required approve_posts permission, bypass moderation queues for their own uploads, and enumerate and delete other users' pending attachments.
- CVSS
- 7.1 HIGH (v3.1, NVD)CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:H/A:L
- Weakness (CWE)
- CWE-863
- Known exploited
- Not in CISA's KEV catalog
- EPSS (exploitation in the next 30 days)
- Not loaded for this CVE
- Assigned by
- Not given
- NVD analysis
- Deferred
- Record last updated
- Jul 14, 2026
- First seen by InfoSec Signals
- Oct 9, 2026
Affected products
No affected products are listed yet.
References
- https://github.com/SimpleMachines/SMF/commit/7d048f8d66aab9af51cd6ee110fbad103cf673e8
- https://github.com/SimpleMachines/SMF/commit/a7875e876a647572dd4c45da881b875092caac3d
- https://github.com/SimpleMachines/SMF/pull/9181
- https://github.com/SimpleMachines/SMF/pull/9182
- https://www.vulncheck.com/advisories/simple-machines-forum-authorization-bypass-via-attachmentapprove-php
The CVE record on cve.org NVD's entry
The CVE record is authoritative. Products marked “from the name” were identified from the CNA's free-text names, not a CPE, and are matched less certainly. This product uses the NVD API but is not endorsed or certified by the NVD.