CVE-2026-81725NLTK before 3.10.3 Regular Expression Denial of Service via Pl196xCorpusReader

Descripción

NLTK before 3.10.3 contains a regular expression denial of service vulnerability in Pl196xCorpusReader that allows attackers to cause quadratic CPU consumption by supplying malformed TEI blocks with many unmatched opening tags. Attackers can exploit lazy regex patterns in the read_block method through public APIs like words() and tagged_words() to force repeated rescans and achieve near-quadratic runtime growth.

Datos: CVE.org, NVD, CISA KEV, FIRST EPSS, Ubuntu. Se publican tal como los indican las fuentes, en inglés.

Productos y versiones afectados

Referencias y parches

• GitHub Security Advisory (GHSA-8mpw-7fpc-4gqj) vendor-advisoryExploitVendor Advisory
• VulnCheck Advisory: NLTK before 3.10.3 Regular Expression Denial of Service via Pl196xCorpusReader third-party-advisoryThird Party Advisory