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CVE-2026-66393

NLTK before 3.9.4 Denial of Service via JSONTaggedDecoder PUBLISHED

Description (CNA)

NLTK versions before 3.9.4 contain an unbounded recursion vulnerability in JSONTaggedDecoder.decode_obj() that allows attackers to cause denial of service by supplying deeply nested JSON structures. Attackers can craft JSON payloads exceeding the recursion limit to trigger an unhandled RecursionError that crashes the Python process.

Affected (CNA)

Vendor / productVersions
nltk / nltkaffected 0 before 3.9.4; unaffected 3.9.4

CWE

CWE-674

References

ADP enrichment

CISA-ADP

No English description supplied.