{"id":"CVE-2026-80206","state":"PUBLISHED","title":"NLTK 3.10.2 Regular Expression Denial of Service via tgrep","description":"NLTK before 3.10.3 contains a regular expression denial of service (ReDoS) vulnerability in the tgrep module. The _tgrep_node_action function compiles user-supplied regular expressions embedded in /regex/ pattern nodes and executes them via re.search against tree node labels without any validation or timeout. 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