CVE-2026-12243

A flaw was found in NLTK. An attacker can exploit a path traversal vulnerability by providing specially crafted input to nltk.data.load or nltk.data.find. This allows the attacker to read arbitrary files accessible to the Python process, leading to information disclosure. The vulnerability arises...

EUVD-2026-40240

NLTK version 3.9.4 is vulnerable to a path traversal attack due to an incomplete fix for GitHub Issue 3504. The UNSAFENOPROTOCOLRE regex in nltk/data.py checks for literal ../ sequences but fails to account for percent-encoded traversal sequences such as ..%2f. The url2pathname function decodes...

CVE-2026-12243 Path Traversal via Percent-Encoding in nltk.data.find() and nltk.data.load()

NLTK version 3.9.4 is vulnerable to a path traversal attack due to an incomplete fix for GitHub Issue 3504. The UNSAFENOPROTOCOLRE regex in nltk/data.py checks for literal ../ sequences but fails to account for percent-encoded traversal sequences such as ..%2f. The url2pathname function decodes...

CVE-2026-54293 NLTK: URL-Encoded Path Traversal in nltk.data.load() Allows Arbitrary Local File Read

NLTK Natural Language Toolkit is a suite of open source Python modules, data sets, and tutorials supporting research and development in Natural Language Processing. Prior to 3.10.0-rc1, nltk.data.load in NLTK is vulnerable to path traversal via URL-encoded path separators and traversal segments...

EUVD-2026-38333

NLTK Natural Language Toolkit is a suite of open source Python modules, data sets, and tutorials supporting research and development in Natural Language Processing. Prior to 3.10.0-rc1, nltk.data.load in NLTK is vulnerable to path traversal via URL-encoded path separators and traversal segments...

CVE-2026-54293

NLTK Natural Language Toolkit is a suite of open source Python modules, data sets, and tutorials supporting research and development in Natural Language Processing. Prior to 3.10.0-rc1, nltk.data.load in NLTK is vulnerable to path traversal via URL-encoded path separators and traversal segments...

Security update for python-nltk (important)

openSUSE Security Update: Security update for python-nltk Announcement ID: openSUSE-SU-2026:0211-1 Rating: important References: 1268526 Cross-References: CVE-2026-54293 Affected Products: openSUSE Backports SLE-15-SP7 An update that fixes one vulnerability is now available. Description: This...

Natural Language Toolkit (NLTK): URL-Encoded Path Traversal in nltk.data.load() Allows Arbitrary Local File Read

Summary nltk.data.load in NLTK is vulnerable to path traversal via URL-encoded path separators and traversal segments when using the nltk: URL scheme. The unsafe-path regex check is performed before url2pathname decodes the %xx sequences a classic decode-after-check / TOCTOU-style flaw, allowing ...

Arbitrary File Read via Percent-Encoded Path Traversal in nltk.data.find() / nltk.data.load() - Incomplete Fix of Issue #3504

This report is not public...

NLTK Data Module - Arbitrary File Read via Dead Security Check

This report is not public...

CVE-2025-7707 World-Writable NLTK Cache Directory Vulnerability in run-llama/llama_index

The llamaindex library version 0.12.33 sets the NLTK data directory to a subdirectory of the codebase by default, which is world-writable in multi-user environments. This configuration allows local users to overwrite, delete, or corrupt NLTK data files, leading to potential denial of service, dat...

PT-2025-41794

Name of the Vulnerable Software and Affected Versions llama index version 0.12.33 Description The software sets the NLTK data directory to a subdirectory of the codebase by default, which is world-writable in multi-user environments. This configuration allows local users to overwrite, delete, or...