{"id":"CVE-2026-33236","summary":"NLTK has a Downloader Path Traversal Vulnerability (AFO) - Arbitrary File Overwrite","details":"NLTK (Natural Language Toolkit) is a suite of open source Python modules, data sets, and tutorials supporting research and development in Natural Language Processing. In versions 3.9.3 and prior, the NLTK downloader does not validate the `subdir` and `id` attributes when processing remote XML index files. Attackers can control a remote XML index server to provide malicious values containing path traversal sequences (such as `../`), which can lead to arbitrary directory creation, arbitrary file creation, and arbitrary file overwrite. Commit 89fe2ec2c6bae6e2e7a46dad65cc34231976ed8a patches the issue.","aliases":["GHSA-469j-vmhf-r6v7"],"modified":"2026-04-10T05:42:39.568063Z","published":"2026-03-20T22:47:10.308Z","related":["CGA-699w-f28r-rmq9"],"database_specific":{"cwe_ids":["CWE-22"],"osv_generated_from":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/33xxx/CVE-2026-33236.json","cna_assigner":"GitHub_M"},"references":[{"type":"ADVISORY","url":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/33xxx/CVE-2026-33236.json"},{"type":"ADVISORY","url":"https://github.com/nltk/nltk/security/advisories/GHSA-469j-vmhf-r6v7"},{"type":"ADVISORY","url":"https://nvd.nist.gov/vuln/detail/CVE-2026-33236"},{"type":"FIX","url":"https://github.com/nltk/nltk/commit/89fe2ec2c6bae6e2e7a46dad65cc34231976ed8a"}],"affected":[{"ranges":[{"type":"GIT","repo":"https://github.com/nltk/nltk","events":[{"introduced":"0"},{"fixed":"89fe2ec2c6bae6e2e7a46dad65cc34231976ed8a"}]}],"versions":["2.0.1rc1","2.0.1rc2","2.0.1rc3","2.0.1rc4","3.0.0b1","3.0.2","3.0.3","3.0.4","3.0.5","3.0a4","3.1","3.2","3.2.1","3.2.2","3.2.3","3.2.4","3.2.5","3.3","3.4","3.4.1","3.4.3","3.4.4","3.5","3.5b1","3.6","3.6.1","3.6.2","3.6.5","3.6.6","3.6.7","3.7","3.8","3.8.1","3.8.2","3.9","3.9.1","3.9.2","3.9.3","v3.9.2"],"database_specific":{"source":"https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2026-33236.json"}}],"schema_version":"1.7.5","severity":[{"type":"CVSS_V3","score":"CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:N/I:H/A:H"}]}