CVE-2026-81723

NLTK versions before 3.10.3 contain a quadratic CPU exhaustion vulnerability in XMLCorpusView._read_xml_fragment() that rescans accumulated XML fragments on every 1 KiB block read. Attackers can provide malformed XML corpus files to cause severe CPU consumption and denial of service through affected readers like BNCCorpusReader.

CVSS v3 3.7 LOW

3.7^/10

CVSS v3 : LOW

Vector :

Exploitability : 2.2 / Impact : 1.4

Attack Vector NETWORK

Attack Complexity HIGH

Privileges Required NONE

User Interaction NONE

Confidentiality Impact NONE

Integrity Impact NONE

Availability Impact LOW

Scope UNCHANGED

References

Link	Resource
https://github.com/nltk/nltk/security/advisories/GHSA-vp2x-qp44-57v7
https://www.vulncheck.com/advisories/nltk-before-3.10.3-quadratic-cpu-exhaustion-via-xmlcorpusview
https://github.com/nltk/nltk/security/advisories/GHSA-vp2x-qp44-57v7

Configurations

No configuration.

History

No history.

Information

Published : 2026-08-27 17:21

Updated : 2026-08-31 19:17

NVD link : CVE-2026-81723

Mitre link : CVE-2026-81723

CVE.ORG link : CVE-2026-81723

JSON object : View

Products Affected

No product.

CWE

CWE-400

Uncontrolled Resource Consumption

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