CVE-2026-33236

Severity CVSS v4.0:
Pending analysis
Type:
CWE-22 Path Traversal
Publication date:
20/03/2026
Last modified:
23/03/2026

Description

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.

Vulnerable products and versions

CPE From Up to
cpe:2.3:a:nltk:nltk:*:*:*:*:*:*:*:* 3.9.3 (including)