CVE-2026-79657 (GCVE-0-2026-79657)

Vulnerability from cvelistv5 – Published: 2026-08-25 11:33 – Updated: 2026-10-08 15:25
VLAI
Title
NLTK before 3.10.3 Remote Code Execution via Unsafe Pickle Deserialization
Summary
NLTK versions before 3.10.3 contain a remote code execution vulnerability in allowlisted pickle loaders that trust entire module namespaces instead of specific safe callables. Attackers can craft malicious pickle payloads invoking dangerous in-namespace functions like ReppTokenizer._execute and numpy.f2py.crackfortran.myeval through pickle REDUCE to execute arbitrary commands during model or tokenizer artifact loading.
Severity
9.3 (Critical)
CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N
9.8 (Critical)
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
SSVC
Exploitation: poc Automatable: yes Technical Impact: total
CISA Coordinator · CISA-ADP (v2.0.3)
Decision recorded 2026-08-25 15:58 UTC
CWE
  • CWE-502 - Deserialization of Untrusted Data
Assigner
VulnCheck CNA under the mitre root
CNA scorecard B 84/100 over 7808 records in the last 180 days details
References
Impacted products
Vendor Product Version CPE status
nltk nltk Affected: 0 , < 3.10.3 (semver)
Unaffected: 3.10.3 (semver)
    cpe:2.3:a:nltk:nltk:*:*:*:*:*:*:*:*
Create a notification for this product.
Date Public
2026-08-11 00:00
Credits
leduckhuong
Show details on NVD website
To clipboard 

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