VULNERABILITY INTELLIGENCE

CVE-2026-80205

CVSS score7.5 HIGH
EPSS probability0.65%
CISA KEVNot currently listed
Published2026-08-26
Last modified2026-09-03
CVSS vectorCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H

Description

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.

Weakness classification

  • disclosure@vulncheck.com: CWE-1333

Primary references