GHSA-6655-6QJP-JX7X Soup Sieve: Exponential ReDoS in selector compilation via \9-run in CSS_ESCAPES/IDENTIFIER

Summary The IDENTIFIER/CSSESCAPES regex cssparser.py:119-124 exhibits exponential backtracking on a run of ambiguous digit-escapes \9 in an attribute-name or tag position of an otherwise well-formed selector. It fires at compile time before the SELECTORLIMIT guard via the public soupsieve.compile...

Soup Sieve: Exponential ReDoS in selector compilation via \9-run in CSS_ESCAPES/IDENTIFIER

Summary The IDENTIFIER/CSSESCAPES regex cssparser.py:119-124 exhibits exponential backtracking on a run of ambiguous digit-escapes \9 in an attribute-name or tag position of an otherwise well-formed selector. It fires at compile time before the SELECTORLIMIT guard via the public soupsieve.compile...