This page tracks the Ubuntu fix status. The vulnerability itself is described on the main CVE page. View CVE-2026-80205 →

UBUNTU-CVE-2026-80205

NLTK versions before 3.10.0 contain a regular expression denial of service vulnerability in Text.findall() and TokenSearcher.findall() methods that ac...

Original description

The description as published by the source.

NLTK versions before 3.10.0 contain a regular expression denial of service vulnerability in Text.findall() and TokenSearcher.findall() methods that accept user-supplied regular expressions without validation or timeout. Attackers can supply crafted regex patterns that cause catastrophic backtracking, resulting in indefinite CPU saturation and denial of service to all users of the Python process.

Source: OSV.dev (Open Source Vulnerabilities) OSV