PYSEC-2026-3752

vendorUSosv
view advisory published 2026-08-27Licence: CC-BY-4.0

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.

01

describes (1)

Related CVEs.

IDseverity exploitable
CVE-2026-81725USlow3.7—
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 malform…
02

references

External citations — patches, advisories, analysis.

scry

Advisories like this name the exposed products attackers go after on your perimeter. See what is exposed on your perimeter with a free passive scan.

Free scan