CVE-2025-71408
Eval injection in NLTK collocations allows arbitrary code execution via CLI args.
Is CVE-2025-71408 being exploited?
Not confirmed. CVE-2025-71408 does not appear in CISA's Known Exploited Vulnerabilities catalog, which records only exploitation that has been observed and reported publicly. That is evidence of absence of a report, not evidence the flaw is unattacked. EPSS currently estimates a 0.20% probability of exploitation in the next 30 days.
How severe is CVE-2025-71408?
CVE-2025-71408 is rated High with a CVSS score of 8.5. Severity describes how bad exploitation would be, not how likely it is: pair it with exploitation evidence before deciding what to patch first.
Is there a patch for CVE-2025-71408?
Yes. A fix has been recorded for CVE-2025-71408. The vendor advisory is the authority on the exact fixed version — apply it from there rather than from a summary.
What does CVE-2025-71408 affect?
CVE-2025-71408 affects NLTK < 3.9.3, nltk.collocations (collocations.py), Python environments using NLTK. Confirm the exact affected versions against the vendor advisory before deciding you are exposed.
What should I do about CVE-2025-71408?
Upgrade NLTK to >= 3.9.3 and avoid running collocations.py with untrusted CLI args.
Exploitation status reflects CISA's KEV catalog as we last synced it. Check the catalog directly.
Arbitrary code execution: attacker controlling command-line args can execute Python and OS commands via eval in collocations.py.
Patch when possible
- affected< 3.9.3
As published in the CVE Program record. A version outside these ranges is not a statement that it is unaffected — vendors sometimes understate a range, and distribution-backported builds carry upstream numbers that do not reflect what was patched into them.