CVE-2026-33236
NLTK has a Downloader Path Traversal Vulnerability (AFO) - Arbitrary File Overwrite
CVSS Score
8.1
EPSS Score
0.0%
EPSS Percentile
0th
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.
| CWE | CWE-22 |
| Vendor | nltk |
| Product | nltk |
| Published | Mar 20, 2026 |
| Last Updated | Mar 23, 2026 |
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CVSS v3 Breakdown
CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:N/I:H/A:H Attack Vector
Network
Attack Complexity
Low
Privileges Required
None
User Interaction
Required
Scope
Unchanged
Confidentiality
None
Integrity
High
Availability
High
Affected Versions
nltk / nltk
<= 3.9.3