nltk Known Vulnerabilities & Fixes
nltk has 5 known security vulnerabilities in PyPI (Python). Upgrade to version 3.10.3 or later to resolve all known issues. Data sourced from OSV, enriched with EPSS exploit probability and CISA KEV.
Low Immediate Risk
No actively exploited vulnerabilities detected. Monitor and update in your next maintenance window.
Recommended safe version: 3.10.3
Upgrading to 3.10.3 or later resolves all 5 known vulnerabilities in nltk. Run: pip install "nltk>=3.10.3"
Is nltk in your project?
Check if you're affected and upgrade to 3.10.3 to stay secure.
Security Summary
- 5 affected version ranges have been identified across these 5 advisories.
- 100% of known issues have a published fixed version.
- Remediation: pip install --upgrade nltk
Vulnerabilities
5 unique vulnerabilities — sorted by exploitation risk (KEV → EPSS → CVSS). Click a CVE/GHSA ID for full details. First disclosed Feb 18, 2026, most recently Sep 8, 2026 (202 days apart).
| CVE / GHSA | Severity | Affected | Fixed In |
|---|---|---|---|
| CVE-2026-79657 NLTK: Allowlisted pickle loaders still permit code execution in current source | CRITICAL | 0.8, 0.9, 0.9.3, 0.9.4 (+64 more) | 3.10.3 |
| CVE-2026-0848 | CRITICAL | 0.8, 0.9, 0.9.3, 0.9.4 (+59 more) | 3.9.3 |
| CVE-2026-79675 NLTK: JVM argument injection bypass via per-call options in the NLTK Stanford wrappers (incomplete fix of CVE-2026-12841) | CRITICAL | 0.8, 0.9, 0.9.3, 0.9.4 (+64 more) | 3.10.3 |
| CVE-2025-14009 NLTK has a Zip Slip Vulnerability | CRITICAL | 0.8, 0.9, 0.9.3, 0.9.4 (+59 more) | 3.9.3 |
| CVE-2026-78683 NLTK: Unsafe Pickle Deserialization in TransitionParser Allows Remote Code Execution | CRITICAL | 0.8, 0.9, 0.9.3, 0.9.4 (+61 more) | 3.10.0 |
About This Data
Vulnerability data for nltk is sourced from the Open Source Vulnerability (OSV) database, aggregating reports from GitHub Advisory Database, NIST NVD, and ecosystem-specific sources.
CVSS (Common Vulnerability Scoring System) scores reflect exploitability and impact. EPSS (Exploit Prediction Scoring System) scores indicate the probability of exploitation within the next 30 days. Vulnerabilities marked with are listed in the CISA Known Exploited Vulnerabilities (KEV) catalog.
Related PyPI (Python) Packages
Other packages in this ecosystem, ranked by shared vulnerabilities where available.
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