EUVD-2026-63729

The URLS regular expression in nltk/tokenize/casual.py, compiled into TweetTokenizer.WORDRE and applied by TweetTokenizer.tokenize, contains a naked-domain branch whose domain-label prefix a-z0-9+?:.-a-z0-9+ is unbounded. Input consisting of many alternating label separators can be partitioned in...

CVE-2026-72818 NLTK TweetTokenizer URL Pattern Backtracks Catastrophically on Naked-Domain-Like Input

The URLS regular expression in nltk/tokenize/casual.py, compiled into TweetTokenizer.WORDRE and applied by TweetTokenizer.tokenize, contains a naked-domain branch whose domain-label prefix a-z0-9+?:.-a-z0-9+ is unbounded. Input consisting of many alternating label separators can be partitioned in...

CVE-2026-72818

The URLS regular expression in nltk/tokenize/casual.py, compiled into TweetTokenizer.WORDRE and applied by TweetTokenizer.tokenize, contains a naked-domain branch whose domain-label prefix a-z0-9+?:.-a-z0-9+ is unbounded. Input consisting of many alternating label separators can be partitioned in...

PT-2026-79260

The URLS regular expression in nltk/tokenize/casual.py, compiled into TweetTokenizer.WORD RE and applied by TweetTokenizer.tokenize, contains a naked-domain branch whose domain-label prefix a-z0-9+?:.-a-z0-9+ is unbounded. Input consisting of many alternating label separators can be partitioned i...