{
  "affected": [
    {
      "ranges": [
        {
          "database_specific": {
            "extracted_events": [
              {
                "introduced": "2.1.0"
              },
              {
                "last_affected": "2.1.7"
              }
            ],
            "source": [
              "AFFECTED_FIELD",
              "REFERENCES"
            ]
          },
          "events": [
            {
              "introduced": "453cbdbaec8e022bb1a582a145edcc6fc0edac0e"
            },
            {
              "fixed": "7d048f8d66aab9af51cd6ee110fbad103cf673e8"
            },
            {
              "fixed": "a7875e876a647572dd4c45da881b875092caac3d"
            }
          ],
          "repo": "https://github.com/simplemachines/smf",
          "type": "GIT"
        }
      ]
    }
  ],
  "database_specific": {
    "cna_assigner": "VulnCheck",
    "cwe_ids": [
      "CWE-863"
    ],
    "osv_generated_from": "https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/39xxx/CVE-2026-39903.json",
    "unresolved_ranges": [
      {
        "extracted_events": [
          {
            "introduced": "3.0.0"
          },
          {
            "last_affected": "3.0.0"
          }
        ],
        "source": "AFFECTED_FIELD"
      }
    ]
  },
  "details": "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.",
  "id": "CVE-2026-39903",
  "modified": "2026-07-16T03:31:04.882162486Z",
  "published": "2026-07-10T16:03:20.983Z",
  "references": [
    {
      "type": "ADVISORY",
      "url": "https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/39xxx/CVE-2026-39903.json"
    },
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2026-39903"
    },
    {
      "type": "ADVISORY",
      "url": "https://www.vulncheck.com/advisories/simple-machines-forum-authorization-bypass-via-attachmentapprove-php"
    },
    {
      "type": "REPORT",
      "url": "https://github.com/SimpleMachines/SMF/pull/9181"
    },
    {
      "type": "REPORT",
      "url": "https://github.com/SimpleMachines/SMF/pull/9182"
    },
    {
      "type": "FIX",
      "url": "https://github.com/SimpleMachines/SMF/commit/7d048f8d66aab9af51cd6ee110fbad103cf673e8"
    },
    {
      "type": "FIX",
      "url": "https://github.com/SimpleMachines/SMF/commit/a7875e876a647572dd4c45da881b875092caac3d"
    },
    {
      "type": "PACKAGE",
      "url": "https://github.com/SimpleMachines/SMF"
    }
  ],
  "schema_version": "1.8.0",
  "severity": [
    {
      "score": "CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:N/VI:H/VA:L/SC:N/SI:N/SA:N",
      "type": "CVSS_V4"
    }
  ],
  "summary": "Simple Machines Forum Authorization Bypass via AttachmentApprove.php"
}