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National Vulnerability Database

National Vulnerability Database

NVD

National Vulnerability Database
  1. Vulnerabilities

CVE-2025-71408 Detail

Description

NLTK (Natural Language Toolkit) before version 3.9.3 contains an eval injection vulnerability in the nltk.collocations module that allows an attacker who controls command-line arguments to execute arbitrary Python code. When collocations.py is invoked directly, the __main__ block passes command-line arguments directly to eval() as suffixes of BigramAssocMeasures without allowlist validation or sanitization, enabling an attacker to supply a Python expression that escapes the intended attribute lookup and executes arbitrary code including OS commands via the os module.


Metrics

 
NVD enrichment efforts reference publicly available information to associate vector strings. CVSS information contributed by other sources is also displayed.
CVSS 4.0 Severity and Vector Strings:

NIST CVSS score
NIST: NVD
N/A
NVD assessment not yet provided.

Nist CVSS score does not match with CNA score
CNA:  VulnCheck
CVSS-B 8.5 HIGH
Vector:  CVSS:4.0/AV:L/AC:L/AT:N/PR:L/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N

References to Advisories, Solutions, and Tools

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URL Source(s) Tag(s)
https://aydinnyunus.github.io/2026/06/07/command-injection-nltk-collocations-eval/ VulnCheck
https://github.com/nltk/nltk/commit/66f14096d952ec8f04934f515e027534bd4eb0ac VulnCheck
https://github.com/nltk/nltk/pull/3465 VulnCheck
https://github.com/nltk/nltk/releases/tag/3.9.3 VulnCheck
https://www.vulncheck.com/advisories/nltk-eval-injection-via-collocations-py-command-line-arguments VulnCheck

Weakness Enumeration

CWE-ID CWE Name Source
CWE-95 Improper Neutralization of Directives in Dynamically Evaluated Code ('Eval Injection') VulnCheck  

Change History

1 change records found show changes

Quick Info

CVE Dictionary Entry:
CVE-2025-71408
NVD Published Date:
07/24/2026
NVD Last Modified:
07/24/2026
Source:
VulnCheck