Symfony: HtmlSanitizer URL Parser Deny Gates Underinclusive: Percent-Encoded BiDi Marks and Unicode Whitespace Bypass Visual-Spoofing Defense
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Symfony is a PHP framework for web and console applications and a set of reusable PHP components. From 6.1.0 until 6.4.41, 7.4.13, and 8.0.13, UrlSanitizer::parse() rejected raw BiDi formatting characters but not percent-encoded forms and used an ASCII-only whitespace check, allowing sanitized URLs to retain visual-spoofing characters that downstream consumers could decode or display. This issue is fixed in versions 6.4.41, 7.4.13, and 8.0.13.
Our own answer: ranges merged, affected separated from platform-only, with confidence and review flags.
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