Duplicate Advisory: Uncontrolled recursion in nltk.featstruct.FeatStructReader causes unhandled RecursionError (DoS) via deeply nested feature-structure input

Duplicate Advisory This advisory has been withdrawn because it is a duplicate of GHSA-cw6x-m8jw-qmrh. This link is maintained to preserve external references. Original Description NLTK before 3.10.3 contains an uncontrolled recursion vulnerability in nltk.featstruct.FeatStructReader that allows...

PYSEC-2026-3739

NLTK before 3.10.3 contains an uncontrolled recursion vulnerability in nltk.featstruct.FeatStructReader that allows unauthenticated attackers to cause a denial of service by supplying deeply nested feature-structure input. Attackers can craft trivial payloads with nested brackets that exceed...

CVE-2026-81724 NLTK before 3.10.3 Denial of Service via Uncontrolled Recursion

NLTK before 3.10.3 contains an uncontrolled recursion vulnerability in nltk.featstruct.FeatStructReader that allows unauthenticated attackers to cause a denial of service by supplying deeply nested feature-structure input. Attackers can craft trivial payloads with nested brackets that exceed...

PT-2026-82619

Name of the Vulnerable Software and Affected Versions NLTK versions prior to 3.10.3 Description An uncontrolled recursion issue exists in the nltk.featstruct.FeatStructReader class. Unauthenticated attackers can trigger a denial of service by providing deeply nested feature-structure input, such ...