[HtmlSanitizer] Honor universal attribute sanitizers, apply maxInputLength to text contexts, document forceAttribute and allowAttribute caveats#64342
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nicolas-grekas merged 1 commit intoMay 23, 2026
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[HtmlSanitizer] Honor universal attribute sanitizers, apply maxInputLength to text contexts, document forceAttribute and allowAttribute caveats#64342nicolas-grekas merged 1 commit intosymfony:6.4symfony/symfony:6.4from nicolas-grekas:hardening-htmlsanitizer-6.4nicolas-grekas/symfony:hardening-htmlsanitizer-6.4Copy head branch name to clipboard
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…ength to text contexts, document forceAttribute and allowAttribute caveats
This was referenced May 27, 2026
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Hardening, not a security fix. Bundles four small improvements surfaced during a recent audit:
DomVisitor::setAttributes()now honors attribute sanitizers registered with the documentednull, nullwildcard pattern fromAttributeSanitizerInterface: the['*']['*']slot is added to thearray_mergeso universal sanitizers actually run.HtmlSanitizer::sanitizeWithContext()appliesmaxInputLengthbefore theCONTEXT_TEXTearly-return path, so text-context calls (sanitizeFor('textarea', …),sanitizeFor('title', …)) cannot exceed the configured limit.HtmlSanitizerConfig::forceAttribute()docblock now documents that the provided value is written verbatim and is not routed through any attribute sanitizer (includingUrlAttributeSanitizer). Callers are responsible for ensuring the value is safe.HtmlSanitizerConfig::allowAttribute()docblock now documents its subtractive nature: it restricts the attribute to the listed elements and removes it from any other allowed element that previously had it. UseallowElement($element, [$attribute])to add an attribute to one element without affecting others.