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CVE-2025-71408Proof of concept (PoC) published · CISA

NLTK < 3.9.3 Eval Injection via collocations.py Command-Line Arguments

CVSS score

8.5

EPSS probability

%0.3

Risk score

0.0

Published

2 mo ago

Official patch verified

Etkilenen ürün ve sürüm için yayımlanan güvenlik güncellemesini uygulayın.

Impact on My Inventory

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Vulnerability description

DayBreach CVE AI Research

CVE-2025-71408 has vendor, distribution, patch and security-source records on file. We can compare them and prepare an explanation linked to the evidence.

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.

IMPACT: Affected Products and Software

Affected Products

The following products are affected by CVE-2025-71408 vulnerability. Where our threat engine knows the exact affected versions, they are listed below.

IDVENDORPRODUCTACTION
1ntlkntlk View
2nltknltk View
3pypinltk View
Total affected vendors: 3|Products: 3

RED HAT CSAF/VEX: Product Impact Check

Red Hat has not yet published a CSAF/VEX impact record for this CVE. This does not mean “not affected”.

SCORING: CVSS from Multiple Sources

CVSS Scores

The Common Vulnerability Scoring System is a standardised framework for assessing the severity of vulnerabilities in software and systems. We collect and display CVSS scores from several sources for each CVE.

SCOREVERSIONSEVERITYVECTORSOURCE
8.5CVSS V40HIGHCVSS:4.0/AV:L/AC:L/AT:N/PR:L/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:XNVD
8.5CVSS 4.0—Vector not publishedGitHub Advisory
8.5CVSS V4_0HIGHCVSS:4.0/AV:L/AC:L/AT:N/PR:L/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:NCVE CNA
7.8CVSS V31HIGHCVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:HNVD
7.8CVSS 3.x—Vector not publishedGitHub Advisory
7.8CVSS V3_1HIGHCVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:HCVE CNA

Patch and Remediation Guide

Solution & Remediation Advisory

Patch verified

10 doğrulanmış yama veya düzeltilmiş sürüm kanıtı bulundu.

nvd

NVD tarafından Patch olarak etiketlenmiş referans

Open source
nvd

NVD tarafından Patch olarak etiketlenmiş referans

Open source
nvd

NVD tarafından Patch olarak etiketlenmiş referans

Open source
osvnltk3.9.3

OSV düzeltilmiş sürüm: 3.9.3

cvelist

NLTK 3.9.3 Release Notes

Open source
cvelist

Pull Request

Open source
cvelist

Patch Commit

Open source
reference

NLTK 3.9.3 Release Notes

Open source
reference

Pull Request

Open source
reference

Patch Commit

Open source
Confirm the affected product and version against the source evidence above.
Restrict access to internet-facing services and apply network segmentation.
Apply the official update named in the evidence only to the matching product and version.
Monitor server logs and network endpoints for signs of anomalous execution.

Public exploit and active exploitation status

Verified exploit intelligence

No verified public PoC, exploit repository or Metasploit module has been found for this CVE yet.

Weakness Classification and Attack Patterns (CWE & CAPEC)

CWE - Common Weakness Enumeration

While CVE identifies specific instances of vulnerabilities, CWE categorises the common flaws or weaknesses that can lead to vulnerabilities. CVE-2025-71408 is associated with the following CWEs:

Common Attack Pattern Enumeration and Classification (CAPEC)

Common Attack Pattern Enumeration and Classification (CAPEC) stores attack patterns, which are descriptions of the common attributes and approaches employed by adversaries to exploit the CVE-2025-71408 weaknesses.

Attack Vector and Accessibility

ExposureYerel erişim
PermissionsLow
UserGerekmiyor

Official Sources and Advisories

CVSS Vector Radar Chart

8.5 / 10
Attack VectorLocalComplexityLowPrivilegesLowUser Interact.NoneConfidentialityLowIntegrityNoneAvailabilityHigh

Vulnerability Scoring Details

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
Attack VectorLocal
Attack ComplexityLow
Privileges RequiredLow privileges
User InteractionNone required
Confidentiality (Gizlilik)Low
Integrity (Bütünlük)None
Availability (Erişilebilirlik)High

Yama doğrulandı

10 doğrulanmış yama veya düzeltilmiş sürüm kanıtı bulundu.

Follow the vendor

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ntlk
N
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nltk
P
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pypi

Weakness Type (CWE & CAPEC)

Similar Vulnerabilities

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