{
    "dataType": "CVE_RECORD",
    "dataVersion": "5.2",
    "cveMetadata": {
        "cveId": "CVE-2026-27199",
        "assignerOrgId": "a0819718-46f1-4df5-94e2-005712e83aaa",
        "state": "PUBLISHED",
        "assignerShortName": "GitHub_M",
        "dateReserved": "2026-02-18T19:47:02.155Z",
        "datePublished": "2026-02-21T05:15:53.335Z",
        "dateUpdated": "2026-02-24T19:02:19.689Z"
    },
    "containers": {
        "cna": {
            "title": "Werkzeug safe_join() allows Windows special device names",
            "problemTypes": [
                {
                    "descriptions": [
                        {
                            "cweId": "CWE-67",
                            "lang": "en",
                            "description": "CWE-67: Improper Handling of Windows Device Names",
                            "type": "CWE"
                        }
                    ]
                }
            ],
            "metrics": [
                {
                    "cvssV4_0": {
                        "attackVector": "NETWORK",
                        "attackComplexity": "LOW",
                        "attackRequirements": "PRESENT",
                        "privilegesRequired": "NONE",
                        "userInteraction": "NONE",
                        "vulnConfidentialityImpact": "NONE",
                        "vulnIntegrityImpact": "NONE",
                        "vulnAvailabilityImpact": "LOW",
                        "subConfidentialityImpact": "NONE",
                        "subIntegrityImpact": "NONE",
                        "subAvailabilityImpact": "NONE",
                        "baseScore": 6.3,
                        "baseSeverity": "MEDIUM",
                        "vectorString": "CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:N/VI:N/VA:L/SC:N/SI:N/SA:N",
                        "version": "4.0"
                    }
                }
            ],
            "references": [
                {
                    "name": "https://github.com/pallets/werkzeug/security/advisories/GHSA-29vq-49wr-vm6x",
                    "tags": [
                        "x_refsource_CONFIRM"
                    ],
                    "url": "https://github.com/pallets/werkzeug/security/advisories/GHSA-29vq-49wr-vm6x"
                },
                {
                    "name": "https://github.com/pallets/werkzeug/commit/f407712fdc60a09c2b3f4fe7db557703e5d9338d",
                    "tags": [
                        "x_refsource_MISC"
                    ],
                    "url": "https://github.com/pallets/werkzeug/commit/f407712fdc60a09c2b3f4fe7db557703e5d9338d"
                },
                {
                    "name": "https://github.com/pallets/werkzeug/releases/tag/3.1.6",
                    "tags": [
                        "x_refsource_MISC"
                    ],
                    "url": "https://github.com/pallets/werkzeug/releases/tag/3.1.6"
                }
            ],
            "affected": [
                {
                    "vendor": "pallets",
                    "product": "werkzeug",
                    "versions": [
                        {
                            "version": "< 3.1.6",
                            "status": "affected"
                        }
                    ]
                }
            ],
            "providerMetadata": {
                "orgId": "a0819718-46f1-4df5-94e2-005712e83aaa",
                "shortName": "GitHub_M",
                "dateUpdated": "2026-02-21T05:15:53.335Z"
            },
            "descriptions": [
                {
                    "lang": "en",
                    "value": "Werkzeug is a comprehensive WSGI web application library. Versions 3.1.5 and below, the safe_join function allows Windows device names as filenames if preceded by other path segments. This was previously reported as GHSA-hgf8-39gv-g3f2, but the added filtering failed to account for the fact that safe_join accepts paths with multiple segments, such as example/NUL. The function send_from_directory uses safe_join to safely serve files at user-specified paths under a directory. If the application is running on Windows, and the requested path ends with a special device name, the file will be opened successfully, but reading will hang indefinitely. This issue has been fixed in version 3.1.6."
                }
            ],
            "source": {
                "advisory": "GHSA-29vq-49wr-vm6x",
                "discovery": "UNKNOWN"
            }
        },
        "adp": [
            {
                "metrics": [
                    {
                        "other": {
                            "type": "ssvc",
                            "content": {
                                "timestamp": "2026-02-24T19:02:05.165135Z",
                                "id": "CVE-2026-27199",
                                "options": [
                                    {
                                        "Exploitation": "none"
                                    },
                                    {
                                        "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": "2026-02-24T19:02:19.689Z"
                }
            }
        ]
    }
}