CVE-2026-33236
HIGH8.1EPSS 0.02%NLTK has a Downloader Path Traversal Vulnerability (AFO) - Arbitrary File Overwrite
Published: 3/19/2026Modified: 4/28/2026
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.
Affected packages (2)
- Debian/nltkfrom 0
- PyPI/nltkfrom 0, <= 3.9.2
CVSS scores
| Source | Version | Severity | Vector |
|---|---|---|---|
| osv | CVSS 3.1 | HIGH8.1 | CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:N/I:H/A:H |
References (5)
- ADVISORYhttps://nvd.nist.gov/vuln/detail/CVE-2026-33236
- ADVISORYhttps://security-tracker.debian.org/tracker/CVE-2026-33236
- PATCHhttps://github.com/nltk/nltk
- WEBhttps://github.com/nltk/nltk/commit/89fe2ec2c6bae6e2e7a46dad65cc34231976ed8a
- WEBhttps://github.com/nltk/nltk/security/advisories/GHSA-469j-vmhf-r6v7