ActiveState Nltk Version 3.4.5+security.2

Version 3.4.5+security.2 2026-06-08

Security Updates Patched:

• Validate zip members before extraction in the downloader to prevent zip-slip
  RCE (nltk#3468) - CVE-2025-14009
• Reject path traversal in downloader package id/subdir from the remote index
  (#89fe2ec) - CVE-2026-33236
• Block path traversal / absolute paths in CorpusReader file access (nltk#3479,
  nltk#3480) - CVE-2026-0847
• Add optional allowed_dir sandbox to util.filestring() (nltk#3485) - CVE-2026-0846
• Bind the WordNet browser server to localhost only (#bbaae83) - CVE-2026-33231
• Escape the reflected word in the WordNet browser "not found" page to prevent
  XSS (#1c3f799) - CVE-2026-33230
• Cap recursion depth in JSONTaggedDecoder.decode_obj to prevent stack
  exhaustion - GHSA-rf74-v2fm-23pw

Security Notes:

• CVE-2024-39705 (pickle deserialization in data/model loading) was assessed
  and is not remediable in place on the 3.4.5 data baseline: upstream resolved
  it by abandoning the pickled data-package format in 3.9 (new *_tab packages),
  which is not available for the 3.4.5 download index. Documented; no code
  change.

nltk 3.4.5.1

This is a patched release of 3.4.5 for continued python 2 support.

This release cherry-picks cve patches:

• Resolve serious ReDoS in PunktSentenceTokenizer (nltk#2869) - CVE-2021-43854
• Resolve ReDoS opportunity by fixing incorrectly specified regex (nltk#2906) - CVE-2021-3842
• Resolved ReDoS vulnerability in Corpus Reader (nltk#2816) - CVE-2021-3828