{
    "dataType": "CVE_RECORD",
    "dataVersion": "5.2",
    "cveMetadata": {
        "cveId": "CVE-2026-49114",
        "assignerOrgId": "9119a7d8-5eab-497f-8521-727c672e3725",
        "state": "PUBLISHED",
        "assignerShortName": "cisa-cg",
        "dateReserved": "2026-05-27T16:19:04.848Z",
        "datePublished": "2026-08-21T16:10:56.241Z",
        "dateUpdated": "2026-08-21T16:43:10.933Z"
    },
    "containers": {
        "cna": {
            "descriptions": [
                {
                    "lang": "en",
                    "value": "In ONNX before 1.21.0, the 'save_external_data' function builds the external-data file path from the model's external_data location field and opens it for writing without 'O_NOFOLLOW/O_EXCL', after a non-atomic 'os.path.isfile()' check. A local attacker with write access to the directory where a victim serializes external data can deterministically pre-plant a symlink that is being followed, causing the victim's write to append to any file the victim can write, e.g. ~/.ssh/authorized_keys, cron files, or application configs. Fixed in 1.21.0."
                }
            ],
            "affected": [
                {
                    "vendor": "ONNX",
                    "product": "ONNX",
                    "defaultStatus": "unknown",
                    "versions": [
                        {
                            "version": "0",
                            "status": "affected",
                            "lessThan": "1.21.0",
                            "versionType": "custom"
                        },
                        {
                            "version": "1.21.0",
                            "status": "unaffected"
                        }
                    ]
                }
            ],
            "problemTypes": [
                {
                    "descriptions": [
                        {
                            "description": "CWE-367 Time-of-check Time-of-use (TOCTOU) Race Condition",
                            "lang": "en",
                            "type": "CWE",
                            "cweId": "CWE-367"
                        }
                    ]
                },
                {
                    "descriptions": [
                        {
                            "description": "CWE-22 Improper Limitation of a Pathname to a Restricted Directory ('Path Traversal')",
                            "lang": "en",
                            "type": "CWE",
                            "cweId": "CWE-22"
                        }
                    ]
                },
                {
                    "descriptions": [
                        {
                            "description": "CWE-59 Improper Link Resolution Before File Access ('Link Following')",
                            "lang": "en",
                            "type": "CWE",
                            "cweId": "CWE-59"
                        }
                    ]
                }
            ],
            "metrics": [
                {
                    "cvssV3_1": {
                        "scope": "UNCHANGED",
                        "version": "3.1",
                        "baseScore": 7.1,
                        "attackVector": "LOCAL",
                        "baseSeverity": "HIGH",
                        "vectorString": "CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:N/I:H/A:H",
                        "integrityImpact": "HIGH",
                        "userInteraction": "REQUIRED",
                        "attackComplexity": "LOW",
                        "availabilityImpact": "HIGH",
                        "privilegesRequired": "NONE",
                        "confidentialityImpact": "NONE"
                    }
                },
                {
                    "cvssV4_0": {
                        "version": "4.0",
                        "baseScore": 6.8,
                        "attackVector": "LOCAL",
                        "baseSeverity": "MEDIUM",
                        "vectorString": "CVSS:4.0/AV:L/AC:L/AT:N/PR:N/UI:A/VC:N/VI:H/VA:H/SC:N/SI:N/SA:N",
                        "userInteraction": "ACTIVE",
                        "attackComplexity": "LOW",
                        "attackRequirements": "NONE",
                        "privilegesRequired": "NONE",
                        "subIntegrityImpact": "NONE",
                        "vulnIntegrityImpact": "HIGH",
                        "subAvailabilityImpact": "NONE",
                        "vulnAvailabilityImpact": "HIGH",
                        "subConfidentialityImpact": "NONE",
                        "vulnConfidentialityImpact": "NONE"
                    }
                },
                {
                    "other": {
                        "type": "ssvc",
                        "content": {
                            "timestamp": "2026-05-27T16:00:11.944488Z",
                            "id": "CVE-2026-49114",
                            "options": [
                                {
                                    "Exploitation": "poc"
                                },
                                {
                                    "Automatable": "no"
                                },
                                {
                                    "Technical Impact": "partial"
                                }
                            ],
                            "role": "CISA Coordinator",
                            "version": "2.0.3"
                        }
                    }
                }
            ],
            "title": "ONNX symlink-following and path-traversal arbitrary file write",
            "references": [
                {
                    "name": "url",
                    "url": "https://github.com/onnx/onnx/security/advisories/GHSA-q56x-g2fj-4rj6",
                    "tags": [
                        "vendor-advisory",
                        "exploit"
                    ]
                },
                {
                    "name": "url",
                    "url": "https://raw.githubusercontent.com/cisagov/CSAF/develop/csaf_files/IT/white/2026/va-26-233-01.json",
                    "tags": [
                        "third-party-advisory"
                    ]
                },
                {
                    "name": "url",
                    "url": "https://www.cve.org/CVERecord?id=CVE-2026-49114",
                    "tags": [
                        "vdb-entry"
                    ]
                }
            ],
            "credits": [
                {
                    "value": "tsigouris007",
                    "lang": "en"
                },
                {
                    "value": "kpatsakis",
                    "lang": "en"
                }
            ],
            "datePublic": "2026-03-31T00:00:00.000Z",
            "providerMetadata": {
                "orgId": "9119a7d8-5eab-497f-8521-727c672e3725",
                "shortName": "cisa-cg",
                "dateUpdated": "2026-08-21T16:10:56.241Z"
            }
        },
        "adp": [
            {
                "metrics": [
                    {
                        "other": {
                            "type": "ssvc",
                            "content": {
                                "timestamp": "2026-08-21T16:42:42.598941Z",
                                "id": "CVE-2026-49114",
                                "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": "2026-08-21T16:43:10.933Z"
                }
            }
        ]
    }
}