CVE-2025-71408

See a problem?
Please try reporting it to the source first.
Source
https://cve.org/CVERecord?id=CVE-2025-71408
Import Source
https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2025-71408.json
JSON Data
https://api.osv.dev/v1/vulns/CVE-2025-71408
Downstream
Published
2026-07-24T21:07:49.610Z
Modified
2026-07-28T03:55:52.200128114Z
Severity
  • 8.5 (High) CVSS_V4 - 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 CVSS Calculator
Summary
NLTK < 3.9.3 Eval Injection via collocations.py Command-Line Arguments
Details

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.

Database specific 
{
    "cna_assigner": "VulnCheck",
    "osv_generated_from": "https://github.com/CVEProject/cvelistV5/tree/main/cves/2025/71xxx/CVE-2025-71408.json",
    "cwe_ids": [
        "CWE-95"
    ]
}
References

Affected packages

Git / github.com/nltk/nltk

Affected ranges

Type
GIT
Repo
https://github.com/nltk/nltk
Events
Introduced
0 Unknown introduced commit / All previous commits are affected
Fixed
4154eb85e832f266660a09286c7e37e308292284
Fixed
66f14096d952ec8f04934f515e027534bd4eb0ac
Database specific 
{
    "extracted_events": [
        {
            "introduced": "0"
        },
        {
            "fixed": "3.9.3"
        }
    ],
    "source": [
        "DESCRIPTION",
        "REFERENCES"
    ]
}

Affected versions

2.*
2.0.1rc1
2.0.1rc2
2.0.1rc3
2.0.1rc4
3.*
3.0.0b1
3.0.2
3.0.3
3.0.4
3.0.5
3.0a4
3.1
3.2
3.2.1
3.2.2
3.2.3
3.2.4
3.2.5
3.3
3.4
3.4.1
3.4.3
3.4.4
3.5
3.5b1
3.6
3.6.1
3.6.2
3.6.5
3.6.6
3.6.7
3.7
3.8
3.8.1
3.8.2
3.9
3.9.1
3.9.2
v3.*
v3.9.2

Database specific

source 
"https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2025-71408.json"