CVE-2026-81725 (GCVE-0-2026-81725)
Vulnerability from cvelistv5
Published
2026-08-27 14:51
Modified
2026-08-28 15:58
CWE
  • CWE-400 - Uncontrolled Resource Consumption
Summary
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.
Impacted products
Vendor Product Version
nltk nltk Version: 0   
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  • Seen: The vulnerability was mentioned, discussed, or seen somewhere by the user.
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