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nltk

3.10.343M downloads/monltk/nltk ↗New releases in your daily digest, changelog included.

Natural Language Toolkit

Last release 1 months ago
12 Aug 2026
Release timing varies
gaps range from 2 weeks to 1.6 years
Rarely documented
notes for 3 of 55 stable releases
1 version withdrawn
withdrawn after publishing
17 years old
69 releases · first in 2009

Release timeline

69 releases since 2009

2009201120132015

Releases

3.10.312 Aug 2026Security
fix(security): sandbox MaltParser's Java execution ( CVE-2026-12252 , CVE-2026-12841)
Version 3.10.3 2026-08-12

docs: wrap Chat-80 HOWTO output

Sandbox Stanford JAR execution to nltk_data directories

Harden path-traversal / file-I/O sandbox: close write-side symlink TOCTOU + shared-temp squat, lock the cluster with a living audit (CWE-22/59/377)

Extend algorithmic-complexity DoS hardening: repo-wide sweep + two-string distances (CWE-407/CWE-400)

Bound unbounded-work DoS in parsers and grammar transforms (CWE-407/674/835)

fix(security): sandbox MaltParser's Java execution (CVE-2026-12252, CVE-2026-12841)

fix(security): trust the system temp dir only when it is private (CWE-377/CWE-378)

fix(security): validate corpus-reader roots against the data sandbox (CWE-73)

fix(security): validate per-call java() options and replace the -XX:/-D allowlist with a minimal one (CWE-88)

Additional security hardening (CWE-407, CWE-426, CWE-427, CWE-502, CWE-59, CWE-776, CWE-918)

Thanks to the following contributors to 3.10.3: Mohammad Favas S, leduckhuong, Ziyu Lin, dougtrainer28-cmyk, Chaitanya Kadian, 0xRenSec, Arpit Jain, Jace, nguyencanhthuong, Liling Tan, medimedi, Eric Kafe.

What's Changed

Sandbox Stanford JAR execution to nltk_data directories by @ekaf in #3743

docs: wrap Chat-80 HOWTO output by @medisean in #3741

ci: sandboxed-open guard + stabilize security tests across platforms/pythons (#3740) by @alvations in #3744

Prepare release 3.10.3 by @ekaf in #3745

New Contributors

@medisean made their first contribution in #3741

Full Changelog: v3.10.2...v3.10.3

3.10.08 Jul 2026Security

fix(security): sparse Alignment index to stop unbounded-allocation DoS (CVE-2026-12837) by @LinZiyuu in #3651

What's Changed

Let TextCat.guess_language return None for ties by @ekaf in #3543
Fix FunctionalCategory.substitute() ignoring substituted direction by @elias-ba in #3547
Fix concurrent download race conditions with file-based locking by @ekaf in #3549
Fix proxy settings ignored by pathsec.urlopen by @ekaf in #3552
Fix CCG variable direction parsing pipeline by @ekaf in #3556
Fix failing CCG unit tests by @ekaf in #3561
Fix CCG variable capture, chart explosion, and type-raising scope bugs by @ekaf in #3557
fix(security): block XML entity expansion (XXE) in downloader by @scruge1 in #3544
Fix _create_token_table skipping last paragraph break transition + regression test by @13rac1 in #3553
ci(deps): bump actions/github-script from 7 to 8 in the github-actions group by @dependabot[bot] in #3546
Add HuggingFace datasets integration (nltk.huggingface) by @alvations in #3569
fix PorterStemmer not using lowercased word in stem() for irregular forms in NLTK mode by @Lemm1 in #3568
ci(deps): bump the github-actions group with 2 updates by @dependabot[bot] in #3572
Fix WordNetObject comparisons for incompatible types by @ekaf in #3570
Align TnT with Brants (2000) specifications by @jhnwnstd in #3564
Avoid KeyError in langnames.py by @ekaf in #3404
Fix TransitionParser sparse index dtype for scikit-learn 1.9 by @ekaf in #3591
Enable ENFORCE by default and harden downloader concurrency by @ekaf in #3593
Use commonpath for downloader path containment on Windows by @ekaf in #3594
Use lexical containment for downloader target paths by @ekaf in #3595
fix(security): prevent DNS-rebinding SSRF in pathsec.urlopen by @LinZiyuu in #3582
fix(security): block URL-encoded path traversal in nltk: resource URLs by @LinZiyuu in #3575
fix(security): block path traversal in NKJPCorpusReader by @LinZiyuu in #3579
fix(security): block path traversal in FramenetCorpusReader.frame() by @LinZiyuu in #3581
fix(security): prevent ReDoS in ReviewsCorpusReader FEATURES regex (CWE-1333) by @LinZiyuu in #3583
Fix remaining corpus reader pathsec gaps before ENFORCE=True RC by @ekaf in #3588
Cache WordNet max depth lazily for lch_similarity() by @ekaf in #3592
Fix remaining post-merge issues from #3477 and #3498 by @ekaf in #3599
Replace unsafe exec() with importlib in utility CLI by @ekaf in #3609
Document NLTK's new security policy by @ekaf in #3597
Check that CI succeeded on the commit a release tag points to by @ekaf in #3506
Prepare release metadata for 3.10.0 by @ekaf in #3610
Fix release workflow CI check for tagged commits by @ekaf in #3611
Fix perfect-agreement edge cases in agreement metrics by @Muhtasim-Munif-Fahim in #3608
fix(security): prevent ReDoS in TextTilingTokenizer paragraph-break regex (CWE-1333) by @LinZiyuu in #3612
fix(security): prevent ReDoS in SensevalCorpusReader _fixXML (CWE-400) by @LinZiyuu in #3614
fix(security): resolve relative MaltParser dir via MALT_PARSER, not the CWD (CWE-426) by @LinZiyuu in #3616
fix(security): bound LogicParser recursion depth to prevent uncaught RecursionError (CWE-674) by @LinZiyuu in #3617
fix(security): resolve relative ReppTokenizer dir via REPP_TOKENIZER, not the CWD (CWE-427) by @LinZiyuu in #3618
fix(security): do not load weka.jar from the CWD (CWE-494) by @LinZiyuu in #3620
fix(security): do not run the senna binary from the CWD (CWE-829) by @LinZiyuu in #3621
fix(security): prevent ReDoS in chunk tag-pattern parsing (CWE-1333) by @LiteshGhute in #3630
Route _download_package() writes through pathsec.open by @ekaf in #3622
fix(security): resolve symlinks in downloader containment check (CWE-59) by @LinZiyuu in #3619
fix(security): use defusedxml in corpus readers to block XML entity-expansion DoS (CWE-776) by @LinZiyuu in #3615
fix(security): stop exponential ReDoS in XMLCorpusView _VALID_XML_RE (CWE-1333) by @LinZiyuu in #3646
fix(security): route read_sents through pathsec sentinel by @ekaf in #3626
Add RELEASE-Github.md documentation by @ekaf in #3627
fix(security): do not run the candc/boxer binary from the CWD (CWE-426) by @LinZiyuu in #3623
fix(security): algorithmic-complexity DoS in DependencyGraph.contains_cycle by @LinZiyuu in #3632
fix(security): bound recursion in PorterStemmer._is_consonant (CWE-674) by @LinZiyuu in #3633
fix(security): close validate/extract path mismatch in pathsec Zip-Slip guard (CWE-22) by @LinZiyuu in #3634
fix(security): validate path in GzipFileSystemPathPointer.open() (CWE-22) by @LinZiyuu in #3635
fix(security): require a session token for WordNet Browser shutdown (CWE-352) by @LinZiyuu in #3637
fix(security): remove quadratic scan in VADER polarity_scores (CWE-407) by @LinZiyuu in #3638
fix(security): bound super-linear n-gram scan in RIBES word_rank_alignment (CWE-407) by @LinZiyuu in #3639
fix(security): route custom_distance through the pathsec sentinel (CWE-22) by @LinZiyuu in #3640
fix(security): stop quadratic ReDoS in CCG lexicon parsing (CWE-1333) by @LinZiyuu in #3641
fix(security): reject CWD-relative binaries in find_binary (CWE-426) by @LinZiyuu in #3642
fix(ci): resolve isort block (#3615) and restore CCG lexicon syntax (#3641) by @LinZiyuu in #3677
fix(security): read XML corpora through the path-pointer sentinel (CWE-22) by @LinZiyuu in #3636
fix(security): cap zip decompression to prevent decompression-bomb DoS (CWE-409) by @LinZiyuu in #3613
fix(security): stop symlink-following arbitrary deletion in Downloader stale-cleanup (CWE-59) by @LinZiyuu in #3643
fix(security): sparse Alignment index to stop unbounded-allocation DoS (CVE-2026-12837) by @LinZiyuu in #3651
fix(security): sparse ConfusionMatrix to stop quadratic-memory DoS (CVE-2026-12839) by @LinZiyuu in #3652
fix(security): bound Model.satisfy quantifier-nesting cost to stop combinatorial DoS (CVE-2026-12840) by @LinZiyuu in #3653
fix(security): bound everygrams default max_len to stop unbounded-allocation DoS (CVE-2026-12861) by @LinZiyuu in #3655
fix(security): route DependencyGraph.load through the pathsec sandbox (CVE-2026-12867) by @LinZiyuu in #3656
fix(security): make Cistem stemmer linear to stop quadratic-time DoS (CVE-2026-12868) by @LinZiyuu in #3658
fix(security): route data.retrieve write through the pathsec sandbox (CVE-2026-12871) by @LinZiyuu in #3659
fix(security): bound DRT resolve_anaphora work to stop quadratic time+memory DoS (CVE-2026-12873) by @LinZiyuu in #3660
fix(security): bound chart parse-tree extraction to stop exponential DoS (CVE-2026-12886) by @LinZiyuu in #3661
fix(security): make valuation separator regex linear to stop quadratic ReDoS (CVE-2026-12890) by @LinZiyuu in #3662
fix(security): make feature-structure rename regex linear to stop quadratic ReDoS (CVE-2026-12919) by @LinZiyuu in #3663
fix: enforce package ownership during ZIP extraction by @ibfavas in #3625
fix(security): block IPv6 transition-embedded internal IPv4 in SSRF filter (NAT64 bypass, CWE-918) by @LinZiyuu in #3644
fix(security): bound generate() derivation-expansion steps to stop unbounded-enumeration DoS (CVE-2026-12864) by @LinZiyuu in #3654
fix(security): bound phrase_extraction default max_phrase_length to stop cubic DoS (CVE-2026-12870) by @LinZiyuu in #3657
Prevent Arbitrary File Write via XML Attribute Injection in nltk.downloader by @ekaf in #3628
Cache CRFTagger feature extraction; harden boundaries and add tests by @jhnwnstd in #3573
Fix duplicated -l short option on nltk tokenize (#3342) by @jbbqqf in #3580
fix(security): make jaro_similarity flagged-position lookup O(1) to stop cubic DoS (CVE-2026-12926) by @LinZiyuu in #3664
fix(security): bound NgramCounter distinct-ngram count to stop unbounded-memory DoS (CVE-2026-12928) by @LinZiyuu in #3665
fix(security): make METEOR word matching linear to stop quadratic-time DoS (CVE-2026-12929) by @LinZiyuu in #3666
fix(security): bound theorem-prover proof search to stop unbounded-search DoS (CWE-400 / CWE-674) by @LinZiyuu in #3667
fix(security): guard CHILDESCorpusReader.convert_age against malformed input (CWE-476) by @LinZiyuu in #3668
fix(security): validate CoNLL / CMUdict reader lines to stop malformed-line crash (CWE-20) by @LinZiyuu in #3669
fix(security): quadratic DoS in NLTK LEPOR alignment by @LinZiyuu in #3670
fix(security): DoS in NLTK PropBank by @LinZiyuu in #3671
fix(security): Denial of service via quadratic complexity in NLTK segmentation metrics by @LinZiyuu in #3672
fix(security): Quadratic-time DoS in NLTK Tree.un_chomsky_normal_form by @LinZiyuu in #3673
fix(security): Quadratic ReDoS in NLTK Text.findall token search by @LinZiyuu in #3674
fix(security): Exponential beta-reduction DoS in NLTK Expression.simplify by @LinZiyuu in #3675
fix(security): Quadratic-memory DoS in NLTK ProjectiveDependencyParser by @LinZiyuu in #3676
fix(security): DoS in NLTK NomBank instance parsing by @LinZiyuu in #3678
fix(security): DoS in NLTK segmentation pk metric via Uncaught divide-by-zero by @LinZiyuu in #3679
fix(security): Quadratic-backtracking ReDoS in NLTK AlpinoCorpusReader._normalize by @LinZiyuu in #3684
fix(security): Quadratic-time DoS in NLTK Markdown corpus reader blockquotes/lists by @LinZiyuu in #3685
fix(security): Quadratic-time DoS in NLTK GDFA by @LinZiyuu in #3686
Use OMW-2.0 with all WordNet versions by @ekaf in #3690
Fix CWE-88 JVM argument injection in java_options (CVE-2026-12841) by @samrigby64 in #3647
fix(security): MaltParser process-wide CWD pollution during parsing (CVE-2026-12614) by @haoami in #3682
fix(security): prevent pickle RCE in TransitionParser model loading (CWE-502) by @LiteshGhute in #3631
ci(deps): bump the github-actions group with 3 updates by @dependabot[bot] in #3691
fix(security): clean Stanford Java wrapper temp files and isolate Java options (CVE-2026-12615) by @haoami in #3683
Enforce restrictive primitive type checking in pathsec wrappers by @ekaf in #3692
Fix EOF handling in IEERCorpusReader to prevent empty document yields by @CHENNA-NAGESH in #3648
Treat missing unzip output as stale by @Muhtasim-Munif-Fahim in #3607
Avoid RIBES zero division on empty inputs by @Muhtasim-Munif-Fahim in #3604
Use os.name for Windows path handling by @Muhtasim-Munif-Fahim in #3605
don't crash chomsky_normal_form on terminals with siblings by @CodingSelim in #3693
allow escaped brackets in Tree.fromstring by @CodingSelim in #3694

New Contributors

@elias-ba made their first contribution in #3547
@scruge1 made their first contribution in #3544
@13rac1 made their first contribution in #3553
@Lemm1 made their first contribution in #3568
@jhnwnstd made their first contribution in #3564
@LinZiyuu made their first contribution in #3582
@Muhtasim-Munif-Fahim made their first contribution in #3608
@LiteshGhute made their first contribution in #3630
@ibfavas made their first contribution in

Note truncated.

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