CVE-2026-81724
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 Python's recursion limit and raise an unhandled RecursionError, crashing applications that parse user-supplied feature structures or feature grammars.
- Affected products
- Nltk
- CVSS 4.0
- 6.9 MEDIUM
- CVSS 3.1
- 5.3 MEDIUM
- Weakness
- CWE-674
- NVD status
- Received
- Published
- 2026-08-27
CVE-2026-81724 at NVD
No indexed exploits for CVE-2026-81724 yet
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No exploit for CVE-2026-81724 has been indexed yet. Our index is built from live traffic and upstream syncs, so this page can only say what it knows — not that no exploit exists.