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CVE-2026-86451 (GCVE-0-2026-86451)

Vulnerability from cvelistv5 – Published: 2026-09-07 12:59 – Updated: 2026-09-07 12:59
VLAI
Title
MISP Event Graph Object Reference Lookup Exposes References from Unauthorized Objects
Summary
Affected versions of MISP allow authenticated users to retrieve object-reference records by UUID through EventGraphTool::get_reference_data() without first checking whether the requester is authorized to view the object the reference belongs to. The vulnerable code queried ObjectReference.uuid directly and returned the matching row whenever it existed. Because no parent-object ACL was applied, a user who knew or obtained a reference UUID could retrieve information associated with an object outside their normal access scope. The commit explicitly states that any object reference could be returned by UUID without authorizing its parent object. The fix retrieves the referenced object's object_id and calls fetchObjectSimple() with the current user. If the user cannot access that parent object, MISP now returns NotFoundException instead of exposing the reference. Version affected: ≤2.5.45
Severity
5.3 (Medium)
CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:L/VI:N/VA:N/SC:N/SI:N/SA:N
CWE
  • CWE-639 - Authorization Bypass Through User-Controlled Key
  • CWE-862 - Missing Authorization
Assigner
References
Impacted products
Vendor Product Version CPE status
MISP MISP Affected: 0 , ≤ 2.5.45 (semver)
guessed Create a notification for this product.
Credits
Scottish Government - National Cyber Team iglocska Claude Opus 5 (1M context)
Show details on NVD website
To clipboard 

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          "programFiles": [
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              "version": "0",
              "versionType": "semver"
            }
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          "type": "finder",
          "value": "Scottish Government - National Cyber Team"
        },
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          "type": "remediation developer",
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          "type": "remediation developer",
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            "Recovery": "NOT_DEFINED",
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            "valueDensity": "NOT_DEFINED",
            "vectorString": "CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:L/VI:N/VA:N/SC:N/SI:N/SA:N",
            "version": "4.0",
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            "vulnerabilityResponseEffort": "NOT_DEFINED"
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    "datePublished": "2026-09-07T12:59:43.472Z",
    "dateReserved": "2026-09-07T12:59:41.676Z",
    "dateUpdated": "2026-09-07T12:59:43.472Z",
    "state": "PUBLISHED"
  },
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  "dataVersion": "5.2",
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  }
}



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