Vulnerability-Lookup

GHSA-62G6-4J9C-6V7P

Vulnerability from github – Published: 2026-07-10 18:32 – Updated: 2026-07-10 18:32

Details

Simple Machines Forum 2.1 prior to 2.1.8 and 3.0 prior to 3.0 Alpha 5 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.

Severity

7.1 (High)


                  
                    CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:H/A:L

7.1 (High)


                  
                    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

Show details on source website

JSON

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{
  "affected": [],
  "aliases": [
    "CVE-2026-39903"
  ],
  "database_specific": {
    "cwe_ids": [
      "CWE-863"
    ],
    "github_reviewed": false,
    "github_reviewed_at": null,
    "nvd_published_at": "2026-07-10T17:16:57Z",
    "severity": "HIGH"
  },
  "details": "Simple Machines Forum 2.1 prior to 2.1.8 and 3.0 prior to 3.0 Alpha 5 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\u0027 pending attachments.",
  "id": "GHSA-62g6-4j9c-6v7p",
  "modified": "2026-07-10T18:32:19Z",
  "published": "2026-07-10T18:32:19Z",
  "references": [
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2026-39903"
    },
    {
      "type": "WEB",
      "url": "https://github.com/SimpleMachines/SMF/pull/9181"
    },
    {
      "type": "WEB",
      "url": "https://github.com/SimpleMachines/SMF/pull/9182"
    },
    {
      "type": "WEB",
      "url": "https://github.com/SimpleMachines/SMF/commit/7d048f8d66aab9af51cd6ee110fbad103cf673e8"
    },
    {
      "type": "WEB",
      "url": "https://github.com/SimpleMachines/SMF/commit/a7875e876a647572dd4c45da881b875092caac3d"
    },
    {
      "type": "WEB",
      "url": "https://www.vulncheck.com/advisories/simple-machines-forum-authorization-bypass-via-attachmentapprove-php"
    }
  ],
  "schema_version": "1.4.0",
  "severity": [
    {
      "score": "CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:H/A:L",
      "type": "CVSS_V3"
    },
    {
      "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/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X",
      "type": "CVSS_V4"
    }
  ]
}

CVE-2026-39903 (GCVE-0-2026-39903)

Vulnerability from cvelistv5 – Published: 2026-07-10 16:03 – Updated: 2026-07-28 01:48 X_Open Source

Title

Simple Machines Forum Authorization Bypass via AttachmentApprove.php

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.

Severity

7.1 (High)


                        
                          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

7.1 (High)


                        
                          CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:H/A:L

SSVC

Exploitation: none Automatable: no Technical Impact: partial

CISA Coordinator · CISA-ADP (v2.0.3)

Decision recorded 2026-07-14 01:56 UTC

CWE

CWE-863 - Incorrect Authorization

Assigner

VulnCheck mitre root

References

5 references

URL	Tags
https://github.com/SimpleMachines/SMF/pull/9182	issue-tracking
https://github.com/SimpleMachines/SMF/pull/9181	issue-tracking
https://github.com/SimpleMachines/SMF/commit/7d04…	patch
https://github.com/SimpleMachines/SMF/commit/a787…	patch
https://www.vulncheck.com/advisories/simple-machi…	third-party-advisory

Impacted products

1 product

Vendor	Product	Version
SimpleMachines	SMF	Affected: 2.1.0 , ≤ 2.1.7 (semver) Unaffected: 7d048f8d66aab9af51cd6ee110fbad103cf673e8 (git) Affected: 3.0.0 (semver) Unaffected: a7875e876a647572dd4c45da881b875092caac3d (git) cpe:2.3:a:simplemachines:simple_machines_forum:::::::: cpe:2.3:a:simplemachines:simple_machines_forum:3.0.0:::::::*

Date Public

2026-04-07 00:00

Credits

Elure (Marasescu Mihnea-Luca) VulnCheck

Show details on NVD website

JSON

To clipboard

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    "adp": [
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        "metrics": [
          {
            "other": {
              "content": {
                "id": "CVE-2026-39903",
                "options": [
                  {
                    "Exploitation": "none"
                  },
                  {
                    "Automatable": "no"
                  },
                  {
                    "Technical Impact": "partial"
                  }
                ],
                "role": "CISA Coordinator",
                "timestamp": "2026-07-14T01:56:17.608329Z",
                "version": "2.0.3"
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        "providerMetadata": {
          "dateUpdated": "2026-07-14T01:57:00.927Z",
          "orgId": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
          "shortName": "CISA-ADP"
        },
        "title": "CISA ADP Vulnrichment"
      }
    ],
    "cna": {
      "affected": [
        {
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          "packageURL": "pkg:github/SimpleMachines/SMF",
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          "vendor": "SimpleMachines",
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              "status": "affected",
              "version": "2.1.0",
              "versionType": "semver"
            },
            {
              "status": "unaffected",
              "version": "7d048f8d66aab9af51cd6ee110fbad103cf673e8",
              "versionType": "git"
            },
            {
              "status": "affected",
              "version": "3.0.0",
              "versionType": "semver"
            },
            {
              "status": "unaffected",
              "version": "a7875e876a647572dd4c45da881b875092caac3d",
              "versionType": "git"
            }
          ]
        }
      ],
      "cpeApplicability": [
        {
          "nodes": [
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              "cpeMatch": [
                {
                  "criteria": "cpe:2.3:a:simplemachines:simple_machines_forum:*:*:*:*:*:*:*:*",
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                },
                {
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              "operator": "OR"
            }
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        }
      ],
      "metrics": [
        {
          "cvssV4_0": {
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            "Recovery": "NOT_DEFINED",
            "Safety": "NOT_DEFINED",
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            "userInteraction": "NONE",
            "valueDensity": "NOT_DEFINED",
            "vectorString": "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",
            "version": "4.0",
            "vulnAvailabilityImpact": "LOW",
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            "vulnerabilityResponseEffort": "NOT_DEFINED"
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          "scenarios": [
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              "lang": "en",
              "value": "GENERAL"
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        },
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          "cvssV3_1": {
            "attackComplexity": "LOW",
            "attackVector": "NETWORK",
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            "confidentialityImpact": "NONE",
            "integrityImpact": "HIGH",
            "privilegesRequired": "LOW",
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              "type": "CWE"
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      "providerMetadata": {
        "dateUpdated": "2026-07-28T01:48:45.607Z",
        "orgId": "83251b91-4cc7-4094-a5c7-464a1b83ea10",
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          "url": "https://www.vulncheck.com/advisories/simple-machines-forum-authorization-bypass-via-attachmentapprove-php"
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      "title": "Simple Machines Forum Authorization Bypass via AttachmentApprove.php",
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    "assignerOrgId": "83251b91-4cc7-4094-a5c7-464a1b83ea10",
    "assignerShortName": "VulnCheck",
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    "datePublished": "2026-07-10T16:03:20.983Z",
    "dateReserved": "2026-04-07T20:57:06.209Z",
    "dateUpdated": "2026-07-28T01:48:45.607Z",
    "state": "PUBLISHED"
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  "dataType": "CVE_RECORD",
  "dataVersion": "5.2"
}

Sightings

Author	Source	Type	Date	Other

Nomenclature

Seen: The vulnerability was mentioned, discussed, or observed by the user.
Confirmed: The vulnerability has been validated from an analyst's perspective.
Published Proof of Concept: A public proof of concept is available for this vulnerability.
Exploited: The vulnerability was observed as exploited by the user who reported the sighting.
Patched: The vulnerability was observed as successfully patched by the user who reported the sighting.
Not exploited: The vulnerability was not observed as exploited by the user who reported the sighting.
Not confirmed: The user expressed doubt about the validity of the vulnerability.
Not patched: The vulnerability was not observed as successfully patched by the user who reported the sighting.

The MITRE ATT&CK techniques below are AI-generated suggestions, inferred from the description of the vulnerability by the CIRCL/vulnerability-attack-technique-classification-roberta-base model, served locally by ML-Gateway. They have not been verified by an analyst and are provided for guidance only.
The approach is described in our paper Mapping CVEs to MITRE ATT&CK Techniques: A Curated Gold-Set Classifier and the Limits of LLM-Assisted Label Expansion.
Browse all ATT&CK techniques and the vulnerabilities related to each.

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Vulnerabilities whose description is nearest to this one in the vector space of the CIRCL/vulnerability-attack-technique-biencoder model. This is a similarity search over the bi-encoder space (plain cosine), not a classification, and it has no measured accuracy.

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GHSA-62G6-4J9C-6V7P

CVE-2026-39903 (GCVE-0-2026-39903)

Tags

Sightings

Nomenclature

Related by attack behaviour