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.
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History
Tue, 01 Sep 2026 12:15:00 +0000
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| Weaknesses | CWE-606 | |
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threat_severity
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threat_severity
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Thu, 27 Aug 2026 18:00:00 +0000
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Thu, 27 Aug 2026 16:45:00 +0000
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| Description | 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. | |
| Title | NLTK before 3.10.3 Denial of Service via Uncontrolled Recursion | |
| First Time appeared |
Nltk
Nltk nltk |
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| Weaknesses | CWE-674 | |
| CPEs | cpe:2.3:a:nltk:nltk:*:*:*:*:*:*:*:* | |
| Vendors & Products |
Nltk
Nltk nltk |
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cvssV3_1
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Status: PUBLISHED
Assigner: VulnCheck
Published: 2026-08-27T14:51:17.358Z
Updated: 2026-08-27T18:29:04.021Z
Reserved: 2026-08-27T11:15:29.420Z
Link: CVE-2026-81724
Updated: 2026-08-27T18:28:39.837Z
Status : Analyzed
Published: 2026-08-27T17:21:03.100
Modified: 2026-08-31T19:06:33.930
Link: CVE-2026-81724