CVE-2026-71513 (GCVE-0-2026-71513)

Vulnerability from cvelistv5 – Published: 2026-08-22 13:34 – Updated: 2026-08-27 16:24
VLAI
Title
NLTK 3.10.0 through 3.10.2 Remote Code Execution via AllowlistUnpickler Dotted-Name Bypass
Summary
NLTK before 3.10.3 contains a remote code execution vulnerability in AllowlistUnpickler that validates only the pickle module string and not the global name, allowing attackers to resolve dotted names by attribute traversal to callables outside the allowlisted namespace. Attackers can craft untrusted transition-parser models that execute arbitrary commands when TransitionParser.parse loads the model through allowlisted_pickle_load.
Severity
8.7 (High)
CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:P/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N
8.8 (High)
CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H
SSVC
Exploitation: none Automatable: no Technical Impact: total
CISA Coordinator · CISA-ADP (v2.0.3)
Decision recorded 2026-08-25 03:56 UTC
CWE
  • CWE-502 - Deserialization of Untrusted Data
Assigner
VulnCheck CNA under the mitre root
CNA scorecard B 84/100 over 6362 records in the last 180 days details
References
Impacted products
Vendor Product Version CPE status
nltk nltk Affected: 3.10.0 , < 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
Tohirov Fazliddin Mahmud o'g'li
Show details on NVD website
To clipboard 

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