Answer in brief
CVE-2026-39903 records a High severity (CVSS 7.1) vulnerability in Simple Machines Forum Authorization Bypass via AttachmentApprove.php. The current sources do not mark it as known exploited. The current feed maps SimpleMachines/SMF (generic). Check affected ranges and fixed versions before updating.
Analysis pending evidence review
HOL Guard separates source facts from reviewed analysis. See the methodology.
CVSS is 7.1. The current sources do not mark it as known exploited. Treat this as a source-backed prioritization signal, not a statement about your environment.
Analysis status
Analysis pending evidence review
Factual feed record only; HOL analysis is not approved for indexing. Read the methodology.
The current feed maps SimpleMachines/SMF (generic). Check affected ranges and fixed versions before updating.
| Package | Affected range | Fixed version |
|---|---|---|
| SimpleMachines/SMFgeneric | 2.1.0 || 3.0.0 | Not reported |
Published upstream
Jul 10, 2026
Evidence: source:cvelist:source_dates:source-dates:recordSource modified
Jul 28, 2026
Evidence: source:cvelist:source_dates:source-dates:recordFirst seen by HOL
Jul 10, 2026
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.
Quoted source text, attributed separately from HOL analysis.
Answer in brief
CVE-2026-39903 records a High severity (CVSS 7.1) vulnerability in Simple Machines Forum Authorization Bypass via AttachmentApprove.php. The current sources do not mark it as known exploited. The current feed maps SimpleMachines/SMF (generic). Check affected ranges and fixed versions before updating.
Analysis pending evidence review
HOL Guard separates source facts from reviewed analysis. See the methodology.
CVSS is 7.1. The current sources do not mark it as known exploited. Treat this as a source-backed prioritization signal, not a statement about your environment.
Analysis status
Analysis pending evidence review
Factual feed record only; HOL analysis is not approved for indexing. Read the methodology.
The current feed maps SimpleMachines/SMF (generic). Check affected ranges and fixed versions before updating.
| Package | Affected range | Fixed version |
|---|---|---|
| SimpleMachines/SMFgeneric | 2.1.0 || 3.0.0 | Not reported |
Published upstream
Jul 10, 2026
Evidence: source:cvelist:source_dates:source-dates:recordSource modified
Jul 28, 2026
Evidence: source:cvelist:source_dates:source-dates:recordFirst seen by HOL
Jul 10, 2026
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.
Quoted source text, attributed separately from HOL analysis.