CVE-2021-3828: Nltk

High severity, CVSS 7.5. EPSS: 1.7% chance of exploitation in the next 30 days.

nltk is vulnerable to Inefficient Regular Expression Complexity

Affected products

• Nltk Nltk: up to and including 3.6.3

Published 2021-09-27. Last modified 2026-06-17.