Vulnerability-Lookup

GHSA-5J56-975F-V5V8

Vulnerability from github – Published: 2026-09-08 15:31 – Updated: 2026-09-09 03:30

Details

XenForo before 2.3.13 contains an unauthenticated information disclosure vulnerability that allows unauthenticated attackers to retrieve private unfurl records by supplying predictable auto-increment primary key IDs to the unfurl endpoint. Attackers can enumerate or predict result IDs and query the endpoint without any session, user, or visibility checks to obtain rendered preview HTML, original URLs, and query strings from private conversations and other restricted content.

Severity

6.1 (Medium)


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

5.1 (Medium)


                  
                    CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:A/VC:N/VI:N/VA:N/SC:L/SI:L/SA:N

Show details on source website

JSON

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{
  "affected": [],
  "aliases": [
    "CVE-2026-73320"
  ],
  "database_specific": {
    "cwe_ids": [
      "CWE-639"
    ],
    "github_reviewed": false,
    "github_reviewed_at": null,
    "nvd_published_at": "2026-09-08T14:17:26Z",
    "severity": "MODERATE"
  },
  "details": "XenForo before 2.3.13 contains an unauthenticated information disclosure vulnerability that allows unauthenticated attackers to retrieve private unfurl records by supplying predictable auto-increment primary key IDs to the unfurl endpoint. Attackers can enumerate or predict result IDs and query the endpoint without any session, user, or visibility checks to obtain rendered preview HTML, original URLs, and query strings from private conversations and other restricted content.",
  "id": "GHSA-5j56-975f-v5v8",
  "modified": "2026-09-09T03:30:36Z",
  "published": "2026-09-08T15:31:55Z",
  "references": [
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2026-73320"
    },
    {
      "type": "WEB",
      "url": "https://bombobombone.github.io/posts/cve-2026-73320"
    },
    {
      "type": "WEB",
      "url": "https://github.com/BomboBombone/CVE-2026-73320"
    },
    {
      "type": "WEB",
      "url": "https://www.vulncheck.com/advisories/xenforo-unauthenticated-information-disclosure-via-unfurl-endpoint"
    },
    {
      "type": "WEB",
      "url": "https://xenforo.com/community/threads/security-fixes-released-for-all-xenforo-and-media-gallery-versions-2-2-0-2-3-12.239856"
    },
    {
      "type": "WEB",
      "url": "https://xenforo.com/community/threads/xenforo-2-3-13-and-add-ons-released-includes-security-fixes.239857"
    }
  ],
  "schema_version": "1.4.0",
  "severity": [
    {
      "score": "CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N",
      "type": "CVSS_V3"
    },
    {
      "score": "CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:A/VC:N/VI:N/VA:N/SC:L/SI:L/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-2026-73320 (GCVE-0-2026-73320)

Vulnerability from cvelistv5 – Published: 2026-09-08 13:19 – Updated: 2026-09-09 01:11

Title

XenForo < 2.3.13 Unauthenticated Information Disclosure via Unfurl Endpoint

Summary

Severity

5.1 (Medium)


                        
                          CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:A/VC:N/VI:N/VA:N/SC:L/SI:L/SA:N

6.1 (Medium)


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

SSVC

Exploitation: none Automatable: no Technical Impact: partial

CISA Coordinator · CISA-ADP (v2.0.3)

Decision recorded 2026-09-08 13:40 UTC

CWE

CWE-639 - Authorization Bypass Through User-Controlled Key

Assigner

VulnCheck mitre root Scorecard

References

5 references

URL	Tags
https://xenforo.com/community/threads/security-fi…	vendor-advisorypatch
https://xenforo.com/community/threads/xenforo-2-3…	release-notes
https://bombobombone.github.io/posts/cve-2026-73320/	technical-description
https://github.com/BomboBombone/CVE-2026-73320	exploit
https://www.vulncheck.com/advisories/xenforo-unau…	third-party-advisory

Impacted products

1 product

Vendor	Product	Version
XenForo	XenForo	Affected: 0 , < 2.3.13 (semver)

Date Public

2026-09-07 00:00

Credits

Marco Paciaroni (BomboBombone) VulnCheck

Show details on NVD website

JSON

To clipboard

{
  "containers": {
    "adp": [
      {
        "metrics": [
          {
            "other": {
              "content": {
                "id": "CVE-2026-73320",
                "options": [
                  {
                    "Exploitation": "none"
                  },
                  {
                    "Automatable": "no"
                  },
                  {
                    "Technical Impact": "partial"
                  }
                ],
                "role": "CISA Coordinator",
                "timestamp": "2026-09-08T13:40:48.936566Z",
                "version": "2.0.3"
              },
              "type": "ssvc"
            }
          }
        ],
        "providerMetadata": {
          "dateUpdated": "2026-09-08T13:41:06.859Z",
          "orgId": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
          "shortName": "CISA-ADP"
        },
        "title": "CISA ADP Vulnrichment"
      }
    ],
    "cna": {
      "affected": [
        {
          "defaultStatus": "unaffected",
          "product": "XenForo",
          "vendor": "XenForo",
          "versions": [
            {
              "lessThan": "2.3.13",
              "status": "affected",
              "version": "0",
              "versionType": "semver"
            }
          ]
        }
      ],
      "credits": [
        {
          "lang": "en",
          "type": "finder",
          "value": "Marco Paciaroni (BomboBombone)"
        },
        {
          "lang": "en",
          "type": "coordinator",
          "value": "VulnCheck"
        }
      ],
      "datePublic": "2026-09-07T00:00:00.000Z",
      "descriptions": [
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        }
      ],
      "metrics": [
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          "cvssV4_0": {
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            "Recovery": "NOT_DEFINED",
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            "attackComplexity": "LOW",
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            "attackVector": "NETWORK",
            "baseScore": 5.1,
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            "exploitMaturity": "NOT_DEFINED",
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            "vulnAvailabilityImpact": "NONE",
            "vulnConfidentialityImpact": "NONE",
            "vulnIntegrityImpact": "NONE",
            "vulnerabilityResponseEffort": "NOT_DEFINED"
          },
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        },
        {
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        {
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        {
          "name": "Researcher PoC",
          "tags": [
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        {
          "tags": [
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      ],
      "source": {
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  "cveMetadata": {
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    "datePublished": "2026-09-08T13:19:57.258Z",
    "dateReserved": "2026-08-11T19:56:20.007Z",
    "dateUpdated": "2026-09-09T01:11:51.781Z",
    "state": "PUBLISHED"
  },
  "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-5J56-975F-V5V8

CVE-2026-73320 (GCVE-0-2026-73320)

Tags

Sightings

Nomenclature

Related by attack behaviour