{
    "dataType": "CVE_RECORD",
    "dataVersion": "5.2",
    "cveMetadata": {
        "cveId": "CVE-2026-70626",
        "assignerOrgId": "83251b91-4cc7-4094-a5c7-464a1b83ea10",
        "state": "PUBLISHED",
        "assignerShortName": "VulnCheck",
        "dateReserved": "2026-08-04T20:17:18.297Z",
        "datePublished": "2026-08-22T14:12:44.983Z",
        "dateUpdated": "2026-08-22T14:12:44.983Z"
    },
    "containers": {
        "cna": {
            "providerMetadata": {
                "orgId": "83251b91-4cc7-4094-a5c7-464a1b83ea10",
                "shortName": "VulnCheck",
                "dateUpdated": "2026-08-22T14:12:44.983Z"
            },
            "datePublic": "2026-08-07T00:00:00.000Z",
            "title": "NLTK before 3.9.4 Symlink Escape via CorpusReader",
            "descriptions": [
                {
                    "lang": "en",
                    "value": "NLTK versions before 3.9.4 contain a symlink escape vulnerability in CorpusReader.open() that allows local attackers to read arbitrary files outside the corpus root. The vulnerability exists because path validation is lexical and does not account for symlink resolution, enabling attackers to place symlinks inside the corpus root to access files outside the intended boundary."
                }
            ],
            "problemTypes": [
                {
                    "descriptions": [
                        {
                            "lang": "en",
                            "description": "Improper Link Resolution Before File Access ('Link Following')",
                            "cweId": "CWE-59",
                            "type": "CWE"
                        }
                    ]
                }
            ],
            "affected": [
                {
                    "vendor": "nltk",
                    "product": "nltk",
                    "defaultStatus": "unaffected",
                    "packageURL": "pkg:pypi/nltk",
                    "versions": [
                        {
                            "version": "0",
                            "status": "affected",
                            "versionType": "semver",
                            "lessThan": "3.9.4"
                        },
                        {
                            "version": "3.9.4",
                            "status": "unaffected",
                            "versionType": "semver"
                        }
                    ]
                }
            ],
            "cpeApplicability": [
                {
                    "nodes": [
                        {
                            "operator": "OR",
                            "negate": false,
                            "cpeMatch": [
                                {
                                    "vulnerable": true,
                                    "criteria": "cpe:2.3:a:nltk:nltk:*:*:*:*:*:*:*:*",
                                    "versionEndExcluding": "3.9.4"
                                }
                            ]
                        }
                    ]
                }
            ],
            "metrics": [
                {
                    "cvssV4_0": {
                        "Automatable": "NOT_DEFINED",
                        "Recovery": "NOT_DEFINED",
                        "Safety": "NOT_DEFINED",
                        "attackComplexity": "LOW",
                        "attackRequirements": "NONE",
                        "attackVector": "LOCAL",
                        "baseScore": 8.6,
                        "baseSeverity": "HIGH",
                        "exploitMaturity": "NOT_DEFINED",
                        "privilegesRequired": "NONE",
                        "providerUrgency": "NOT_DEFINED",
                        "subAvailabilityImpact": "NONE",
                        "subConfidentialityImpact": "NONE",
                        "subIntegrityImpact": "NONE",
                        "userInteraction": "NONE",
                        "valueDensity": "NOT_DEFINED",
                        "vectorString": "CVSS:4.0/AV:L/AC:L/AT:N/PR:N/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N",
                        "version": "4.0",
                        "vulnAvailabilityImpact": "HIGH",
                        "vulnConfidentialityImpact": "HIGH",
                        "vulnIntegrityImpact": "HIGH",
                        "vulnerabilityResponseEffort": "NOT_DEFINED"
                    },
                    "format": "CVSS"
                },
                {
                    "cvssV3_1": {
                        "attackComplexity": "LOW",
                        "attackVector": "LOCAL",
                        "availabilityImpact": "NONE",
                        "baseScore": 6.2,
                        "baseSeverity": "MEDIUM",
                        "confidentialityImpact": "HIGH",
                        "integrityImpact": "NONE",
                        "privilegesRequired": "NONE",
                        "scope": "UNCHANGED",
                        "userInteraction": "NONE",
                        "vectorString": "CVSS:3.1/AV:L/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N",
                        "version": "3.1"
                    },
                    "format": "CVSS"
                }
            ],
            "references": [
                {
                    "url": "https://github.com/nltk/nltk/security/advisories/GHSA-r6gq-whwq-mvg9",
                    "tags": [
                        "vendor-advisory"
                    ],
                    "name": "GitHub Security Advisory (GHSA-r6gq-whwq-mvg9)"
                },
                {
                    "name": "VulnCheck Advisory: NLTK before 3.9.4 Symlink Escape via CorpusReader",
                    "tags": [
                        "third-party-advisory"
                    ],
                    "url": "https://www.vulncheck.com/advisories/nltk-before-symlink-escape-via-corpusreader"
                }
            ],
            "credits": [
                {
                    "lang": "en",
                    "value": "leduckhuong",
                    "type": "reporter"
                }
            ],
            "x_generator": {
                "engine": "vulncheck-endgame"
            }
        }
    }
}