PYSEC-2026-597

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...

UBUNTU-CVE-2026-12243

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...