YesWiki before 4.6.7 SQL Injection via filtertags filterN parameter

YesWiki before 4.6.7 contains an SQL injection vulnerability in the Bazar filtertags action, which wraps unescaped filterN attribute tokens in quotes and concatenates them into a raw tags.value IN (...) clause. Unauthenticated attackers on default installs can save filtertags markup in a page with a trailing-backslash token that breaks quote parity under MySQL backslash escaping. This lets them inject a five-column UNION subquery to read arbitrary table data such as password hashes.