CVE-2026-39903

Summary

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.

Affected Software

VendorProductVersion RangeStatus
SimpleMachinesSMF2.1.0 <= 2.1.7affected
SimpleMachinesSMF7d048f8d66aab9af51cd6ee110fbad103cf673e8unaffected
SimpleMachinesSMF3.0.0affected
SimpleMachinesSMFa7875e876a647572dd4c45da881b875092caac3dunaffected

Weaknesses

  • CWE-863: Incorrect Authorization

ADP Enrichment

CISA ADP Vulnrichment

  • SSVC:
  • Exploitation: none
    • Automatable: no
    • Technical Impact: partial

References