{
    "dataType": "CVE_RECORD",
    "dataVersion": "5.2",
    "cveMetadata": {
        "cveId": "CVE-2026-6684",
        "assignerOrgId": "44488dab-36db-4358-99f9-bc116477f914",
        "state": "PUBLISHED",
        "assignerShortName": "runZero",
        "dateReserved": "2026-04-20T15:06:20.061Z",
        "datePublished": "2026-07-01T13:45:03.639Z",
        "dateUpdated": "2026-07-01T15:25:53.071Z"
    },
    "containers": {
        "cna": {
            "providerMetadata": {
                "orgId": "44488dab-36db-4358-99f9-bc116477f914",
                "shortName": "runZero",
                "dateUpdated": "2026-07-01T14:10:58.544Z"
            },
            "title": "FatFs Infinite Loop in GPT Partition Scan",
            "datePublic": "2026-07-01T13:00:00.000Z",
            "problemTypes": [
                {
                    "descriptions": [
                        {
                            "lang": "en",
                            "cweId": "CWE-835",
                            "description": "CWE-835 Loop with unreachable exit condition ('infinite loop')",
                            "type": "CWE"
                        }
                    ]
                }
            ],
            "affected": [
                {
                    "vendor": "ChaN",
                    "product": "FatFs",
                    "versions": [
                        {
                            "status": "affected",
                            "version": "0",
                            "lessThan": "R0.16",
                            "versionType": "custom"
                        }
                    ],
                    "defaultStatus": "unaffected"
                }
            ],
            "descriptions": [
                {
                    "lang": "en",
                    "value": "FatFs prior to R0.16 that use GPT scanning with 'FF_LBA64 = 1' contains an issue where an unbounded loop count derived from GPT header field GPTH_PtNum, enabling extremely long or effectively infinite mount-time scans. This maps to CWE-835 (Loop with Unreachable Exit Condition). Estimated CVSS v3.1 vector: CVSS:3.1/AV:P/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H (4.6, Medium). The estimated CISA SSVC vectors are Exploitation: PoC, Technical Impact: Partial.",
                    "supportingMedia": [
                        {
                            "type": "text/html",
                            "base64": false,
                            "value": "<p>FatFs prior to R0.16 that use GPT scanning with 'FF_LBA64 = 1' contains an issue where an unbounded loop count derived from GPT header field GPTH_PtNum, enabling extremely long or effectively infinite mount-time scans. This maps to CWE-835 (Loop with Unreachable Exit Condition). Estimated CVSS v3.1 vector: CVSS:3.1/AV:P/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H (4.6, Medium). The estimated CISA SSVC vectors are Exploitation: PoC, Technical Impact: Partial.<br><br></p>"
                        }
                    ]
                }
            ],
            "references": [
                {
                    "url": "https://www.runzero.com/blog/fatfs-bugs/",
                    "tags": [
                        "third-party-advisory"
                    ]
                },
                {
                    "url": "https://github.com/runZeroInc/vulns-2026-fatfs-chance",
                    "tags": [
                        "technical-description"
                    ]
                },
                {
                    "url": "https://elm-chan.org/fsw/ff/",
                    "tags": [
                        "product"
                    ]
                },
                {
                    "url": "https://www.runzero.com/advisories/fatfs-gpt-scan-loop-dos-cve-2026-6684/",
                    "tags": [
                        "third-party-advisory"
                    ]
                }
            ],
            "metrics": [
                {
                    "format": "CVSS",
                    "scenarios": [
                        {
                            "lang": "en",
                            "value": "GENERAL"
                        }
                    ],
                    "cvssV3_1": {
                        "version": "3.1",
                        "attackVector": "PHYSICAL",
                        "attackComplexity": "LOW",
                        "privilegesRequired": "NONE",
                        "userInteraction": "NONE",
                        "scope": "UNCHANGED",
                        "confidentialityImpact": "NONE",
                        "integrityImpact": "NONE",
                        "availabilityImpact": "HIGH",
                        "baseSeverity": "MEDIUM",
                        "baseScore": 4.6,
                        "vectorString": "CVSS:3.1/AV:P/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H"
                    }
                }
            ],
            "credits": [
                {
                    "lang": "en",
                    "value": "HD Moore of runZero, Inc.",
                    "type": "finder"
                },
                {
                    "lang": "en",
                    "value": "Tod Beardsley of runZero, Inc.",
                    "type": "coordinator"
                }
            ],
            "source": {
                "discovery": "UNKNOWN"
            },
            "x_generator": {
                "engine": "Vulnogram 1.0.2"
            }
        },
        "adp": [
            {
                "references": [
                    {
                        "url": "https://github.com/runZeroInc/vulns-2026-fatfs-chance",
                        "tags": [
                            "exploit"
                        ]
                    }
                ],
                "metrics": [
                    {
                        "other": {
                            "type": "ssvc",
                            "content": {
                                "timestamp": "2026-07-01T15:25:35.369745Z",
                                "id": "CVE-2026-6684",
                                "options": [
                                    {
                                        "Exploitation": "poc"
                                    },
                                    {
                                        "Automatable": "no"
                                    },
                                    {
                                        "Technical Impact": "partial"
                                    }
                                ],
                                "role": "CISA Coordinator",
                                "version": "2.0.3"
                            }
                        }
                    }
                ],
                "title": "CISA ADP Vulnrichment",
                "providerMetadata": {
                    "orgId": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
                    "shortName": "CISA-ADP",
                    "dateUpdated": "2026-07-01T15:25:53.071Z"
                }
            }
        ]
    }
}