CVE-2026-33236

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.

CVSS v3 8.1 HIGH

8.1^/10

CVSS v3 : HIGH

Vector :

Exploitability : 2.8 / Impact : 5.2

Attack Vector NETWORK

Attack Complexity LOW

Privileges Required NONE

User Interaction REQUIRED

Confidentiality Impact NONE

Integrity Impact HIGH

Availability Impact HIGH

Scope UNCHANGED

References

Link	Resource
https://github.com/nltk/nltk/commit/89fe2ec2c6bae6e2e7a46dad65cc34231976ed8a	Patch
https://github.com/nltk/nltk/security/advisories/GHSA-469j-vmhf-r6v7	Exploit Vendor Advisory

Configurations

Configuration 1 (hide)

cpe:2.3:a:nltk:nltk:*:*:*:*:*:*:*:*

History

No history.

Information

Published : 2026-03-20 23:16

Updated : 2026-03-23 19:15

NVD link : CVE-2026-33236

Mitre link : CVE-2026-33236

CVE.ORG link : CVE-2026-33236

JSON object : View

Products Affected

nltk

nltk

CWE

CWE-22

Improper Limitation of a Pathname to a Restricted Directory ('Path Traversal')

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