Safe SVG

Yes, this can be done using the svg_allowed_attributes and svg_allowed_tags filters. They take one argument that must be returned. See below for examples: add_filter( 'svg_allowed_attributes', function ( $attributes ) { // Do what you want here... // This should return an array so add your attributes to // to the $attributes array before returning it. E.G. $attributes[] = 'target'; // This would allow the target="" attribute. return $attributes; } ); add_filter( 'svg_allowed_tags', function ( $tags ) { // Do what you want here... // This should return an array so add your tags to // to the $tags array before returning it. E.G. $tags[] = 'use'; // This would allow the element. return $tags; } );

Mostly, yes. The Inline SVG block renders an SVG that carries its own <style> element inside a shadow root, because CSS inside an inline SVG is otherwise applied to the whole page rather than just the SVG. Stylesheets cannot reach into a shadow root, so theme CSS such as .entry-content svg { fill: red; } will not apply to those SVGs. Inherited properties still cross the boundary, so setting color on an ancestor and using currentColor inside the SVG works, as do CSS custom properties. SVGs that do not contain a <style> element are rendered without the shadow root and can be styled by theme stylesheets. To turn isolation off, at the cost of allowing an SVG's CSS to affect the rest of the page: add_filter( 'safe_svg_inline_use_shadow_dom', '__return_false' );

Safe SVG only allows SVGs through upload paths it can actively sanitize. While most WordPress uploads use standard functions like wp_handle_upload() (which Safe SVG hooks), plugins and themes can create custom upload paths by calling WordPress's underlying _wp_handle_upload() function with arbitrary action parameters. Globally enabling the image/svg+xml MIME type would allow SVGs through all upload paths—including custom ones Safe SVG cannot intercept and sanitize. This would create security vulnerabilities where unsanitized SVGs containing malicious scripts could be uploaded. This is a deliberate design decision: Safe SVG prioritizes guaranteed sanitization over broad compatibility. SVGs are only allowed when we can ensure they're safe.

Please report security bugs found in the source code of the Safe SVG plugin through the Patchstack Vulnerability Disclosure  Program. The Patchstack team will assist you with verification, CVE assignment, and notify the developers of this plugin.